From 954d51cfbe05902df39d0a18d1ecb0c881b27ad3 Mon Sep 17 00:00:00 2001 From: Alexander Ebert Date: Sat, 19 Sep 2015 19:50:53 +0200 Subject: [PATCH] Switch from LESS -> SCSS (wip) --- .../install/files/acp/templates/styleAdd.tpl | 35 +- .../acp/templates/styleVariableColor.tpl | 2 +- .../files/lib/acp/form/StyleAddForm.class.php | 161 +- .../install/files/lib/system/WCF.class.php | 7 +- .../lib/system/style/StyleCompiler.class.php | 78 +- .../files/lib/system/style/lessc.inc.php | 3675 -------------- .../lib/system/style/scssphp/classmap.php | 63 + .../lib/system/style/scssphp/scss.inc.php | 21 + .../system/style/scssphp/src/Base/Range.php | 47 + .../lib/system/style/scssphp/src/Colors.php | 176 + .../lib/system/style/scssphp/src/Compiler.php | 4457 +++++++++++++++++ .../system/style/scssphp/src/Formatter.php | 167 + .../style/scssphp/src/Formatter/Compact.php | 44 + .../scssphp/src/Formatter/Compressed.php | 89 + .../style/scssphp/src/Formatter/Crunched.php | 76 + .../style/scssphp/src/Formatter/Expanded.php | 56 + .../style/scssphp/src/Formatter/Nested.php | 145 + .../lib/system/style/scssphp/src/Parser.php | 2342 +++++++++ .../lib/system/style/scssphp/src/Server.php | 454 ++ .../lib/system/style/scssphp/src/Util.php | 55 + .../lib/system/style/scssphp/src/Version.php | 22 + .../install/files/style/bootstrap/mixin.less | 78 - .../install/files/style/bootstrap/mixin.scss | 61 + .../bootstrap/{reset.less => reset.scss} | 0 .../style/element/{list.less => list.scss} | 4 +- .../layout/{content.less => content.scss} | 16 +- .../style/layout/{global.less => global.scss} | 35 +- .../style/layout/{layout.less => layout.scss} | 37 +- .../{navigation.less => navigation.scss} | 4 +- .../{pageFooter.less => pageFooter.scss} | 55 +- .../{pageHeader.less => pageHeader.scss} | 16 +- .../layout/{sidebar.less => sidebar.scss} | 2 +- .../files/style/ui/{alert.less => alert.scss} | 0 .../ui/{breadcrumb.less => breadcrumb.scss} | 4 +- .../style/ui/{button.less => button.scss} | 42 +- .../style/ui/{message.less => message.scss} | 54 +- 36 files changed, 8626 insertions(+), 3954 deletions(-) delete mode 100644 wcfsetup/install/files/lib/system/style/lessc.inc.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/classmap.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/scss.inc.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Base/Range.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Colors.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Compiler.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Formatter.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compact.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compressed.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Crunched.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Expanded.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Nested.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Parser.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Server.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Util.php create mode 100644 wcfsetup/install/files/lib/system/style/scssphp/src/Version.php delete mode 100644 wcfsetup/install/files/style/bootstrap/mixin.less create mode 100644 wcfsetup/install/files/style/bootstrap/mixin.scss rename wcfsetup/install/files/style/bootstrap/{reset.less => reset.scss} (100%) rename wcfsetup/install/files/style/element/{list.less => list.scss} (93%) rename wcfsetup/install/files/style/layout/{content.less => content.scss} (65%) rename wcfsetup/install/files/style/layout/{global.less => global.scss} (65%) rename wcfsetup/install/files/style/layout/{layout.less => layout.scss} (72%) rename wcfsetup/install/files/style/layout/{navigation.less => navigation.scss} (96%) rename wcfsetup/install/files/style/layout/{pageFooter.less => pageFooter.scss} (62%) rename wcfsetup/install/files/style/layout/{pageHeader.less => pageHeader.scss} (91%) rename wcfsetup/install/files/style/layout/{sidebar.less => sidebar.scss} (95%) rename wcfsetup/install/files/style/ui/{alert.less => alert.scss} (100%) rename wcfsetup/install/files/style/ui/{breadcrumb.less => breadcrumb.scss} (81%) rename wcfsetup/install/files/style/ui/{button.less => button.scss} (60%) rename wcfsetup/install/files/style/ui/{message.less => message.scss} (79%) diff --git a/wcfsetup/install/files/acp/templates/styleAdd.tpl b/wcfsetup/install/files/acp/templates/styleAdd.tpl index 3ab155d864..fa54d34152 100644 --- a/wcfsetup/install/files/acp/templates/styleAdd.tpl +++ b/wcfsetup/install/files/acp/templates/styleAdd.tpl @@ -396,10 +396,26 @@ {* colors *}
+ {foreach from=$colors key=itemPrefix item=items} +
+

{$itemPrefix}

+ + {foreach from=$items item=colorItems} +
    + {foreach from=$colorItems[items] item=colorItem} + {capture assign=variableName}{if $colorItems[overridePrefix]|isset}{@$colorItems[overridePrefix]}{else}{@$itemPrefix}{/if}{@$colorItem|ucfirst}{/capture} + +
  • {include file='styleVariableColor' variableName=$variableName languageVariable=$colorItem}
    • + {/foreach} +
+ {/foreach} +
+ {/foreach} + {*
{lang}wcf.acp.style.colors.page{/lang} - {* page *} + {* page *}{*
  • {include file='styleVariableColor' variableName='wcfPageBackgroundColor' languageVariable='backgroundColor'}
  • {include file='styleVariableColor' variableName='wcfPageColor' languageVariable='color'}
    • @@ -415,7 +431,7 @@
    {lang}wcf.acp.style.colors.content{/lang} - {* content *} + {* content *}{*
    • {include file='styleVariableColor' variableName='wcfContentBackgroundColor' languageVariable='backgroundColor'}
    • {include file='styleVariableColor' variableName='wcfColor' languageVariable='color'}
      • @@ -432,7 +448,7 @@
      {lang}wcf.acp.style.colors.container{/lang} - {* general *} + {* general *}{*
      • {include file='styleVariableColor' variableName='wcfContainerBackgroundColor' languageVariable='backgroundColor'}
      • {include file='styleVariableColor' variableName='wcfContainerAccentBackgroundColor' languageVariable='accentBackgroundColor'}
        • @@ -448,7 +464,7 @@
        {lang}wcf.acp.style.colors.userPanel{/lang} - {* user panel *} + {* user panel *}{*
        • {include file='styleVariableColor' variableName='wcfUserPanelBackgroundColor' languageVariable='backgroundColor'}
        • {include file='styleVariableColor' variableName='wcfUserPanelColor' languageVariable='color'}
          • @@ -464,7 +480,7 @@
          {lang}wcf.acp.style.colors.tabular{/lang} - {* general *} + {* general *}{*
          • {include file='styleVariableColor' variableName='wcfTabularBoxBackgroundColor' languageVariable='backgroundColor'}
          • {include file='styleVariableColor' variableName='wcfTabularBoxColor' languageVariable='color'}
            • @@ -479,7 +495,7 @@
            {lang}wcf.acp.style.colors.buttons{/lang} - {* default button *} + {* default button *}{*
            • {include file='styleVariableColor' variableName='wcfButtonBackgroundColor' languageVariable='backgroundColor'}
            • {include file='styleVariableColor' variableName='wcfButtonBorderColor' languageVariable='borderColor'}
              • @@ -488,7 +504,7 @@ {event name='defaultButtonColorListItems'}
            - {* button:hover *} + {* button:hover *}{*
            • {include file='styleVariableColor' variableName='wcfButtonHoverBackgroundColor' languageVariable='hoverBackgroundColor'}
            • {include file='styleVariableColor' variableName='wcfButtonHoverBorderColor' languageVariable='hoverBorderColor'}
              • @@ -497,7 +513,7 @@ {event name='hoverButtonColorListItems'}
            - {* primary button *} + {* primary button *}{*
            • {include file='styleVariableColor' variableName='wcfButtonPrimaryBackgroundColor' languageVariable='primaryBackgroundColor'}
            • {include file='styleVariableColor' variableName='wcfButtonPrimaryBorderColor' languageVariable='primaryBorderColor'}
              • @@ -512,7 +528,7 @@
              {lang}wcf.acp.style.colors.formInput{/lang} - {* form input *} + {* form input *}{*
              • {include file='styleVariableColor' variableName='wcfInputBackgroundColor' languageVariable='backgroundColor'}
              • {include file='styleVariableColor' variableName='wcfInputBorderColor' languageVariable='borderColor'}
                • @@ -527,6 +543,7 @@
              {event name='colorFieldsets'} + *}
{* advanced *} diff --git a/wcfsetup/install/files/acp/templates/styleVariableColor.tpl b/wcfsetup/install/files/acp/templates/styleVariableColor.tpl index 272e871dbe..6c67e55f2d 100644 --- a/wcfsetup/install/files/acp/templates/styleVariableColor.tpl +++ b/wcfsetup/install/files/acp/templates/styleVariableColor.tpl @@ -2,7 +2,7 @@
{lang}wcf.acp.style.colors.{$languageVariable}{/lang}
- @{$variableName} + ${$variableName}
diff --git a/wcfsetup/install/files/lib/acp/form/StyleAddForm.class.php b/wcfsetup/install/files/lib/acp/form/StyleAddForm.class.php index 6e86490149..f88202b308 100644 --- a/wcfsetup/install/files/lib/acp/form/StyleAddForm.class.php +++ b/wcfsetup/install/files/lib/acp/form/StyleAddForm.class.php @@ -47,7 +47,7 @@ class StyleAddForm extends AbstractForm { * list of available font families * @var array */ - public $availableFontFamilies = array( + public $availableFontFamilies = [ 'Arial, Helvetica, sans-serif' => 'Arial', 'Chicago, Impact, Compacta, sans-serif' => 'Chicago', '"Comic Sans MS", sans-serif' => 'Comic Sans', @@ -61,25 +61,25 @@ class StyleAddForm extends AbstractForm { '"Times New Roman", Times, Georgia, serif' => 'Times New Roman', '"Trebuchet MS", Arial, sans-serif' => 'Trebuchet MS', 'Verdana, Helvetica, sans-serif' => 'Verdana' - ); + ]; /** * list of available template groups * @var array<\wcf\data\template\group\TemplateGroup> */ - public $availableTemplateGroups = array(); + public $availableTemplateGroups = []; /** * list of available units * @var array */ - public $availableUnits = array('px', 'em', '%', 'pt'); + public $availableUnits = ['px', 'em', '%', 'pt']; /** * list of color variables * @var array */ - public $colors = array(); + public $colors = []; /** * copyright message @@ -91,7 +91,7 @@ class StyleAddForm extends AbstractForm { * list of global variables * @var array */ - public $globals = array(); + public $globals = []; /** * image path @@ -114,7 +114,7 @@ class StyleAddForm extends AbstractForm { /** * @see \wcf\page\AbstractPage::$neededPermissions */ - public $neededPermissions = array('admin.style.canManageStyle'); + public $neededPermissions = ['admin.style.canManageStyle']; /** * style package name @@ -162,13 +162,13 @@ class StyleAddForm extends AbstractForm { * list of variables and their value * @var array */ - public $variables = array(); + public $variables = []; /** * list of specialized variables * @var array */ - public $specialVariables = array(); + public $specialVariables = []; /** * @see \wcf\page\IPage::readParameters() @@ -204,9 +204,20 @@ class StyleAddForm extends AbstractForm { I18nHandler::getInstance()->readValues(); + // @TODO + $colors = []; + foreach ($this->colors as $k => $v) { + foreach ($v as $vv) { + $prefix = (isset($vv['overridePrefix'])) ? $vv['overridePrefix'] : $k; + foreach ($vv['items'] as $vvv) { + $colors[] = $prefix . ucfirst($vvv); + } + } + } + // ignore everything except well-formed rgba() $regEx = new Regex('rgba\(\d{1,3}, \d{1,3}, \d{1,3}, (1|1\.00?|0|0?\.[0-9]{1,2})\)'); - foreach ($this->colors as $variableName) { + foreach ($colors as $variableName) { if (isset($_POST[$variableName]) && $regEx->match($_POST[$variableName])) { $this->variables[$variableName] = $_POST[$variableName]; } @@ -329,14 +340,14 @@ class StyleAddForm extends AbstractForm { FROM wcf".WCF_N."_style_variable"; $statement = WCF::getDB()->prepareStatement($sql); $statement->execute(); - $variables = array(); + $variables = []; while ($row = $statement->fetchArray()) { $variables[] = $row['variableName']; } $lines = explode("\n", StringUtil::unifyNewlines($this->variables['overrideLess'])); $regEx = new Regex('^@([a-zA-Z]+): ?([@a-zA-Z0-9 ,\.\(\)\%\#-]+);$'); - $errors = array(); + $errors = []; foreach ($lines as $index => &$line) { $line = StringUtil::trim($line); @@ -351,17 +362,17 @@ class StyleAddForm extends AbstractForm { // cannot override variables covered by style editor if (in_array($matches[1], $this->colors) || in_array($matches[1], $this->globals) || in_array($matches[1], $this->specialVariables)) { - $errors[] = array( + $errors[] = [ 'error' => 'predefined', 'text' => $matches[1] - ); + ]; } else if (!in_array($matches[1], $variables)) { // unknown style variable - $errors[] = array( + $errors[] = [ 'error' => 'unknown', 'text' => $matches[1] - ); + ]; } else { $this->variables[$matches[1]] = $matches[2]; @@ -369,10 +380,10 @@ class StyleAddForm extends AbstractForm { } else { // not valid - $errors[] = array( + $errors[] = [ 'error' => 'notValid', 'text' => $line - ); + ]; } } @@ -418,7 +429,90 @@ class StyleAddForm extends AbstractForm { */ protected function setVariables() { // set color variables - $this->colors = array( + $this->colors = [ + 'wcfPage' => [ + [ + 'overridePrefix' => 'wcfHeader', + 'items' => ['background', 'text', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfMenu', + 'items' => ['background', 'backgroundActive', 'border', 'text', 'textActive', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfMenuContent', + 'items' => ['background', 'backgroundActive', 'border', 'text', 'textActive', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfSearchBox', + 'items' => ['background', 'backgroundActive', 'border', 'borderActive', 'text', 'textActive', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfHeaderBox', + 'items' => ['background', 'text', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfHeaderNavigation', + 'items' => ['background', 'text', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfFooterBox', + 'items' => ['background', 'text', 'link', 'linkActive'] + ], + [ + 'overridePrefix' => 'wcfFooter', + 'items' => ['background', 'text', 'link', 'linkActive'] + ] + ], + 'wcfContent' => [ + [ + 'items' => ['background', 'text', 'link', 'linkActive', 'border'], + ], + [ + 'overridePrefix' => 'wcfContentHeadline', + 'items' => ['text', 'link', 'linkActive'] + ], + [ + 'items' => ['textDimmed', 'linkDimmed', 'linkDimmedActive'] + ], + [ + 'items' => ['backgroundAccent', 'textAccent', 'linkAccent', 'linkAccentActive', 'borderAccent'] + ] + ], + 'wcfSidebar' => [ + [ + 'items' => ['background', 'border'] + ], + [ + 'overridePrefix' => 'wcfSidebarBox', + 'items' => ['background', 'text', 'link', 'linkActive', 'border', 'textDimmed', 'linkDimmed', 'linkDimmedActive'] + ], + [ + 'overridePrefix' => 'wcfSidebarBoxHeadline', + 'items' => ['text', 'link', 'linkActive', 'border'] + ] + ], + 'wcfButton' => [ + [ + 'items' => ['background', 'backgroundActive', 'text', 'textActive', 'border', 'borderActive'] + ], + [ + 'items' => ['backgroundAccent', 'backgroundAccentActive', 'textAccent', 'textAccentActive', 'borderAccent', 'borderAccentActive'] + ] + ], + 'wcfInput' => [ + [ + 'items' => ['background', 'backgroundActive', 'border', 'borderActive', 'text', 'textActive'] + ] + ], + 'wcfDropdown' => [ + [ + 'items' => ['background', 'backgroundActive', 'text', 'textActive', 'link', 'linkActive'] + ] + ] + ]; + /* + $this->colors = [ 'wcfButtonBackgroundColor', 'wcfButtonBorderColor', 'wcfButtonColor', @@ -453,24 +547,24 @@ class StyleAddForm extends AbstractForm { 'wcfUserPanelColor', 'wcfUserPanelHoverBackgroundColor', 'wcfUserPanelHoverColor', - ); - + ]; + */ // set global variables - $this->globals = array( + $this->globals = [ 'wcfBaseFontSize', 'wcfLayoutFixedWidth', 'wcfLayoutMinWidth', 'wcfLayoutMaxWidth' - ); + ]; // set specialized variables - $this->specialVariables = array( + $this->specialVariables = [ 'individualLess', 'overrideLess', 'pageLogo', 'useFluidLayout', 'wcfBaseFontFamily' - ); + ]; EventHandler::getInstance()->fireAction($this, 'setVariables'); } @@ -494,8 +588,8 @@ class StyleAddForm extends AbstractForm { public function save() { parent::save(); - $this->objectAction = new StyleAction(array(), 'create', array( - 'data' => array_merge($this->additionalFields, array( + $this->objectAction = new StyleAction([], 'create', [ + 'data' => array_merge($this->additionalFields, [ 'styleName' => $this->styleName, 'templateGroupID' => $this->templateGroupID, 'packageName' => $this->packageName, @@ -509,10 +603,10 @@ class StyleAddForm extends AbstractForm { 'license' => $this->license, 'authorName' => $this->authorName, 'authorURL' => $this->authorURL - )), + ]), 'tmpHash' => $this->tmpHash, 'variables' => $this->variables - )); + ]); $returnValues = $this->objectAction->executeAction(); $style = $returnValues['returnValues']; @@ -520,9 +614,9 @@ class StyleAddForm extends AbstractForm { I18nHandler::getInstance()->save('styleDescription', 'wcf.style.styleDescription'.$style->styleID, 'wcf.style'); $styleEditor = new StyleEditor($style); - $styleEditor->update(array( + $styleEditor->update([ 'styleDescription' => 'wcf.style.styleDescription'.$style->styleID - )); + ]); // call saved event $this->saved(); @@ -551,13 +645,14 @@ class StyleAddForm extends AbstractForm { I18nHandler::getInstance()->assignVariables(); - WCF::getTPL()->assign(array( + WCF::getTPL()->assign([ 'action' => 'add', 'authorName' => $this->authorName, 'authorURL' => $this->authorURL, 'availableFontFamilies' => $this->availableFontFamilies, 'availableTemplateGroups' => $this->availableTemplateGroups, 'availableUnits' => $this->availableUnits, + 'colors' => $this->colors, 'copyright' => $this->copyright, 'imagePath' => $this->imagePath, 'isTainted' => $this->isTainted, @@ -570,6 +665,6 @@ class StyleAddForm extends AbstractForm { 'templateGroupID' => $this->templateGroupID, 'tmpHash' => $this->tmpHash, 'variables' => $this->variables - )); + ]); } } diff --git a/wcfsetup/install/files/lib/system/WCF.class.php b/wcfsetup/install/files/lib/system/WCF.class.php index 7007493502..d5867af46f 100644 --- a/wcfsetup/install/files/lib/system/WCF.class.php +++ b/wcfsetup/install/files/lib/system/WCF.class.php @@ -233,8 +233,10 @@ class WCF { * * @param \Exception $e */ - public static final function handleException(\Exception $e) { + public static final function handleException($e) { try { + if (!($e instanceof \Exception)) throw $e; + if ($e instanceof IPrintableException) { $e->show(); exit; @@ -243,6 +245,9 @@ class WCF { // repack Exception self::handleException(new SystemException($e->getMessage(), $e->getCode(), '', $e)); } + catch (\Throwable $exception) { + die("
WCF::handleException() Unhandled exception: ".$exception->getMessage()."\n\n".$exception->getTraceAsString());
+		}
 		catch (\Exception $exception) {
 			die("
WCF::handleException() Unhandled exception: ".$exception->getMessage()."\n\n".$exception->getTraceAsString());
 		}
diff --git a/wcfsetup/install/files/lib/system/style/StyleCompiler.class.php b/wcfsetup/install/files/lib/system/style/StyleCompiler.class.php
index 1861769da1..8cd5cb4772 100644
--- a/wcfsetup/install/files/lib/system/style/StyleCompiler.class.php
+++ b/wcfsetup/install/files/lib/system/style/StyleCompiler.class.php
@@ -13,7 +13,7 @@ use wcf\util\StringUtil;
 use wcf\util\StyleUtil;
 
 /**
- * Provides access to the LESS PHP compiler.
+ * Provides access to the SCSS PHP compiler.
  * 
  * @author	Alexander Ebert
  * @copyright	2001-2015 WoltLab GmbH
@@ -24,8 +24,8 @@ use wcf\util\StyleUtil;
  */
 class StyleCompiler extends SingletonFactory {
 	/**
-	 * less compiler object
-	 * @var	\lessc
+	 * SCSS compiler object
+	 * @var	\Leafo\ScssPhp\Compiler
 	 */
 	protected $compiler = null;
 	
@@ -33,26 +33,26 @@ class StyleCompiler extends SingletonFactory {
 	 * names of option types which are supported as additional variables
 	 * @var	array
 	 */
-	public static $supportedOptionType = array('boolean', 'integer');
+	public static $supportedOptionType = ['boolean', 'integer'];
 	
 	/**
 	 * @see	\wcf\system\SingletonFactory::init()
 	 */
 	protected function init() {
-		require_once(WCF_DIR.'lib/system/style/lessc.inc.php');
-		$this->compiler = new \lessc();
-		$this->compiler->setImportDir(array(WCF_DIR));
+		require_once(WCF_DIR.'lib/system/style/scssphp/scss.inc.php');
+		$this->compiler = new \Leafo\ScssPhp\Compiler();
+		$this->compiler->setImportPaths([WCF_DIR]);
 	}
 	
 	/**
-	 * Compiles LESS stylesheets.
+	 * Compiles SCSS stylesheets.
 	 * 
 	 * @param	\wcf\data\style\Style	$style
 	 */
 	public function compile(Style $style) {
 		// read stylesheets by dependency order
 		$conditions = new PreparedStatementConditionBuilder();
-		$conditions->add("filename REGEXP ?", ['style/([a-zA-Z0-9\_\-\.]+)\.less']);
+		$conditions->add("filename REGEXP ?", ['style/([a-zA-Z0-9\_\-\.]+)\.(less|scss)']);
 		
 		// TESTING ONLY
 		$conditions->add("packageID <> ?", [1]);
@@ -97,10 +97,10 @@ class StyleCompiler extends SingletonFactory {
 		
 		// get style variables
 		$variables = $style->getVariables();
-		$individualLess = '';
-		if (isset($variables['individualLess'])) {
-			$individualLess = $variables['individualLess'];
-			unset($variables['individualLess']);
+		$individualScss = '';
+		if (isset($variables['individualScss'])) {
+			$individualScss = $variables['individualScss'];
+			unset($variables['individualScss']);
 		}
 		
 		// add style image path
@@ -112,21 +112,21 @@ class StyleCompiler extends SingletonFactory {
 		$variables['style_image_path'] = "'{$imagePath}'";
 		
 		// apply overrides
-		if (isset($variables['overrideLess'])) {
-			$lines = explode("\n", StringUtil::unifyNewlines($variables['overrideLess']));
+		if (isset($variables['overrideScss'])) {
+			$lines = explode("\n", StringUtil::unifyNewlines($variables['overrideScss']));
 			foreach ($lines as $line) {
 				if (preg_match('~^@([a-zA-Z]+): ?([@a-zA-Z0-9 ,\.\(\)\%\#-]+);$~', $line, $matches)) {
 					$variables[$matches[1]] = $matches[2];
 				}
 			}
-			unset($variables['overrideLess']);
+			unset($variables['overrideScss']);
 		}
 		
 		$this->compileStylesheet(
 			WCF_DIR.'style/style-'.$style->styleID,
 			$files,
 			$variables,
-			$individualLess,
+			$individualScss,
 			new Callback(function($content) use ($style) {
 				return "/* stylesheet for '".$style->styleName."', generated on ".gmdate('r')." -- DO NOT EDIT */\n\n" . $content;
 			})
@@ -134,7 +134,7 @@ class StyleCompiler extends SingletonFactory {
 	}
 	
 	/**
-	 * Compiles LESS stylesheets for ACP usage.
+	 * Compiles SCSS stylesheets for ACP usage.
 	 */
 	public function compileACP() {
 		$files = glob(WCF_DIR.'style/*.less');
@@ -145,7 +145,7 @@ class StyleCompiler extends SingletonFactory {
 			ORDER BY	variableID ASC";
 		$statement = WCF::getDB()->prepareStatement($sql);
 		$statement->execute();
-		$variables = array();
+		$variables = [];
 		while ($row = $statement->fetchArray()) {
 			$value = $row['defaultValue'];
 			if (empty($value)) {
@@ -156,7 +156,7 @@ class StyleCompiler extends SingletonFactory {
 		}
 		
 		// insert blue temptation files
-		array_unshift($files, WCF_DIR.'acp/style/blueTemptation/variables.less', WCF_DIR.'acp/style/blueTemptation/override.less');
+		array_unshift($files, WCF_DIR.'acp/style/blueTemptation/variables.scss', WCF_DIR.'acp/style/blueTemptation/override.scss');
 		
 		$variables['style_image_path'] = "'../images/blueTemptation/'";
 		
@@ -164,7 +164,7 @@ class StyleCompiler extends SingletonFactory {
 			WCF_DIR.'acp/style/style',
 			$files,
 			$variables,
-			file_get_contents(WCF_DIR.'acp/style/blueTemptation/individual.less'),
+			file_get_contents(WCF_DIR.'acp/style/blueTemptation/individual.scss'),
 			new Callback(function($content) {
 				// fix relative paths
 				$content = str_replace('../font/', '../../font/', $content);
@@ -184,19 +184,19 @@ class StyleCompiler extends SingletonFactory {
 	 */
 	protected function bootstrap(array $variables) {
 		// add reset like a boss
-		$content = $this->prepareFile(WCF_DIR.'style/bootstrap/reset.less');
+		$content = $this->prepareFile(WCF_DIR.'style/bootstrap/reset.scss');
 		
 		// apply style variables
 		$this->compiler->setVariables($variables);
 		
 		// add mixins
-		$content .= $this->prepareFile(WCF_DIR.'style/bootstrap/mixin.less');
+		$content .= $this->prepareFile(WCF_DIR.'style/bootstrap/mixin.scss');
 		
 		return $content;
 	}
 	
 	/**
-	 * Prepares a LESS stylesheet for importing.
+	 * Prepares a SCSS stylesheet for importing.
 	 * 
 	 * @param	string		$filename
 	 * @return	string
@@ -212,16 +212,16 @@ class StyleCompiler extends SingletonFactory {
 	}
 	
 	/**
-	 * Compiles LESS stylesheets into one CSS-stylesheet and writes them
+	 * Compiles SCSS stylesheets into one CSS-stylesheet and writes them
 	 * to filesystem. Please be aware not to append '.css' within $filename!
 	 * 
 	 * @param	string			$filename
 	 * @param	array		$files
 	 * @param	array		$variables
-	 * @param	string			$individualLess
+	 * @param	string			$individualScss
 	 * @param	\wcf\system\Callback	$callback
 	 */
-	protected function compileStylesheet($filename, array $files, array $variables, $individualLess, Callback $callback) {
+	protected function compileStylesheet($filename, array $files, array $variables, $individualScss, Callback $callback) {
 		foreach ($variables as &$value) {
 			if (StringUtil::startsWith($value, '../')) {
 				$value = '~"'.$value.'"';
@@ -229,7 +229,7 @@ class StyleCompiler extends SingletonFactory {
 		}
 		unset($value);
 		
-		// add options as LESS variables
+		// add options as SCSS variables
 		if (PACKAGE_ID) {
 			foreach (Option::getOptions() as $constantName => $option) {
 				if (in_array($option->optionType, static::$supportedOptionType)) {
@@ -244,28 +244,29 @@ class StyleCompiler extends SingletonFactory {
 			$variables['wcf_option_signature_max_image_height'] = '~"150"';
 		}
 		
-		// build LESS bootstrap
-		$less = $this->bootstrap($variables);
+		// build SCSS bootstrap
+		$scss = $this->bootstrap($variables);
 		foreach ($files as $file) {
-			$less .= $this->prepareFile($file);
+			$scss .= $this->prepareFile($file);
 		}
 		
-		// append individual CSS/LESS
-		if ($individualLess) {
-			$less .= $individualLess;
+		// append individual CSS/SCSS
+		if ($individualScss) {
+			$scss .= $individualScss;
 		}
 		
 		try {
-			$content = $this->compiler->compile($less);
+			$this->compiler->setFormatter('Leafo\ScssPhp\Formatter\Crunched');
+			$content = $this->compiler->compile($scss);
 		}
 		catch (\Exception $e) {
-			throw new SystemException("Could not compile LESS: ".$e->getMessage(), 0, '', $e);
+			throw new SystemException("Could not compile SCSS: ".$e->getMessage(), 0, '', $e);
 		}
 		
 		$content = $callback($content);
 		
 		// compress stylesheet
-		$lines = explode("\n", $content);
+		/*$lines = explode("\n", $content);
 		$content = $lines[0] . "\n" . $lines[1] . "\n";
 		for ($i = 2, $length = count($lines); $i < $length; $i++) {
 			$line = trim($lines[$i]);
@@ -285,13 +286,14 @@ class StyleCompiler extends SingletonFactory {
 				$content .= "\n";
 			}
 		}
+		*/
 		
 		// write stylesheet
 		file_put_contents($filename.'.css', $content);
 		FileUtil::makeWritable($filename.'.css');
 		
 		// convert stylesheet to RTL
-		$content = StyleUtil::convertCSSToRTL($content);
+		//$content = StyleUtil::convertCSSToRTL($content);
 		
 		// write stylesheet for RTL
 		file_put_contents($filename.'-rtl.css', $content);
diff --git a/wcfsetup/install/files/lib/system/style/lessc.inc.php b/wcfsetup/install/files/lib/system/style/lessc.inc.php
deleted file mode 100644
index 478302c1ce..0000000000
--- a/wcfsetup/install/files/lib/system/style/lessc.inc.php
+++ /dev/null
@@ -1,3675 +0,0 @@
-
- * Licensed under MIT or GPLv3, see LICENSE
- */
-
-
-/**
- * The less compiler and parser.
- *
- * Converting LESS to CSS is a three stage process. The incoming file is parsed
- * by `lessc_parser` into a syntax tree, then it is compiled into another tree
- * representing the CSS structure by `lessc`. The CSS tree is fed into a
- * formatter, like `lessc_formatter` which then outputs CSS as a string.
- *
- * During the first compile, all values are *reduced*, which means that their
- * types are brought to the lowest form before being dump as strings. This
- * handles math equations, variable dereferences, and the like.
- *
- * The `parse` function of `lessc` is the entry point.
- *
- * In summary:
- *
- * The `lessc` class creates an intstance of the parser, feeds it LESS code,
- * then transforms the resulting tree to a CSS tree. This class also holds the
- * evaluation context, such as all available mixins and variables at any given
- * time.
- *
- * The `lessc_parser` class is only concerned with parsing its input.
- *
- * The `lessc_formatter` takes a CSS tree, and dumps it to a formatted string,
- * handling things like indentation.
- */
-class lessc {
-	static public $VERSION = "v0.4.0";
-	static protected $TRUE = array("keyword", "true");
-	static protected $FALSE = array("keyword", "false");
-
-	protected $libFunctions = array();
-	protected $registeredVars = array();
-	protected $preserveComments = false;
-
-	public $vPrefix = '@'; // prefix of abstract properties
-	public $mPrefix = '$'; // prefix of abstract blocks
-	public $parentSelector = '&';
-
-	public $importDisabled = false;
-	public $importDir = '';
-
-	protected $numberPrecision = null;
-
-	protected $allParsedFiles = array();
-
-	// set to the parser that generated the current line when compiling
-	// so we know how to create error messages
-	protected $sourceParser = null;
-	protected $sourceLoc = null;
-
-	static public $defaultValue = array("keyword", "");
-
-	static protected $nextImportId = 0; // uniquely identify imports
-
-	// attempts to find the path of an import url, returns null for css files
-	protected function findImport($url) {
-		foreach ((array)$this->importDir as $dir) {
-			$full = $dir.(substr($dir, -1) != '/' ? '/' : '').$url;
-			if ($this->fileExists($file = $full.'.less') || $this->fileExists($file = $full)) {
-				return $file;
-			}
-		}
-
-		return null;
-	}
-
-	protected function fileExists($name) {
-		return is_file($name);
-	}
-
-	static public function compressList($items, $delim) {
-		if (!isset($items[1]) && isset($items[0])) return $items[0];
-		else return array('list', $delim, $items);
-	}
-
-	static public function preg_quote($what) {
-		return preg_quote($what, '/');
-	}
-
-	protected function tryImport($importPath, $parentBlock, $out) {
-		if ($importPath[0] == "function" && $importPath[1] == "url") {
-			$importPath = $this->flattenList($importPath[2]);
-		}
-
-		$str = $this->coerceString($importPath);
-		if ($str === null) return false;
-
-		$url = $this->compileValue($this->lib_e($str));
-
-		// don't import if it ends in css
-		if (substr_compare($url, '.css', -4, 4) === 0) return false;
-
-		$realPath = $this->findImport($url);
-
-		if ($realPath === null) return false;
-
-		if ($this->importDisabled) {
-			return array(false, "/* import disabled */");
-		}
-
-		if (isset($this->allParsedFiles[realpath($realPath)])) {
-			return array(false, null);
-		}
-
-		$this->addParsedFile($realPath);
-		$parser = $this->makeParser($realPath);
-		$root = $parser->parse(file_get_contents($realPath));
-
-		// set the parents of all the block props
-		foreach ($root->props as $prop) {
-			if ($prop[0] == "block") {
-				$prop[1]->parent = $parentBlock;
-			}
-		}
-
-		// copy mixins into scope, set their parents
-		// bring blocks from import into current block
-		// TODO: need to mark the source parser	these came from this file
-		foreach ($root->children as $childName => $child) {
-			if (isset($parentBlock->children[$childName])) {
-				$parentBlock->children[$childName] = array_merge(
-					$parentBlock->children[$childName],
-					$child);
-			} else {
-				$parentBlock->children[$childName] = $child;
-			}
-		}
-
-		$pi = pathinfo($realPath);
-		$dir = $pi["dirname"];
-
-		list($top, $bottom) = $this->sortProps($root->props, true);
-		$this->compileImportedProps($top, $parentBlock, $out, $parser, $dir);
-
-		return array(true, $bottom, $parser, $dir);
-	}
-
-	protected function compileImportedProps($props, $block, $out, $sourceParser, $importDir) {
-		$oldSourceParser = $this->sourceParser;
-
-		$oldImport = $this->importDir;
-
-		// TODO: this is because the importDir api is stupid
-		$this->importDir = (array)$this->importDir;
-		array_unshift($this->importDir, $importDir);
-
-		foreach ($props as $prop) {
-			$this->compileProp($prop, $block, $out);
-		}
-
-		$this->importDir = $oldImport;
-		$this->sourceParser = $oldSourceParser;
-	}
-
-	/**
-	 * Recursively compiles a block.
-	 *
-	 * A block is analogous to a CSS block in most cases. A single LESS document
-	 * is encapsulated in a block when parsed, but it does not have parent tags
-	 * so all of it's children appear on the root level when compiled.
-	 *
-	 * Blocks are made up of props and children.
-	 *
-	 * Props are property instructions, array tuples which describe an action
-	 * to be taken, eg. write a property, set a variable, mixin a block.
-	 *
-	 * The children of a block are just all the blocks that are defined within.
-	 * This is used to look up mixins when performing a mixin.
-	 *
-	 * Compiling the block involves pushing a fresh environment on the stack,
-	 * and iterating through the props, compiling each one.
-	 *
-	 * See lessc::compileProp()
-	 *
-	 */
-	protected function compileBlock($block) {
-		switch ($block->type) {
-		case "root":
-			$this->compileRoot($block);
-			break;
-		case null:
-			$this->compileCSSBlock($block);
-			break;
-		case "media":
-			$this->compileMedia($block);
-			break;
-		case "directive":
-			$name = "@" . $block->name;
-			if (!empty($block->value)) {
-				$name .= " " . $this->compileValue($this->reduce($block->value));
-			}
-
-			$this->compileNestedBlock($block, array($name));
-			break;
-		default:
-			$this->throwError("unknown block type: $block->type\n");
-		}
-	}
-
-	protected function compileCSSBlock($block) {
-		$env = $this->pushEnv();
-
-		$selectors = $this->compileSelectors($block->tags);
-		$env->selectors = $this->multiplySelectors($selectors);
-		$out = $this->makeOutputBlock(null, $env->selectors);
-
-		$this->scope->children[] = $out;
-		$this->compileProps($block, $out);
-
-		$block->scope = $env; // mixins carry scope with them!
-		$this->popEnv();
-	}
-
-	protected function compileMedia($media) {
-		$env = $this->pushEnv($media);
-		$parentScope = $this->mediaParent($this->scope);
-
-		$query = $this->compileMediaQuery($this->multiplyMedia($env));
-
-		$this->scope = $this->makeOutputBlock($media->type, array($query));
-		$parentScope->children[] = $this->scope;
-
-		$this->compileProps($media, $this->scope);
-
-		if (count($this->scope->lines) > 0) {
-			$orphanSelelectors = $this->findClosestSelectors();
-			if (!is_null($orphanSelelectors)) {
-				$orphan = $this->makeOutputBlock(null, $orphanSelelectors);
-				$orphan->lines = $this->scope->lines;
-				array_unshift($this->scope->children, $orphan);
-				$this->scope->lines = array();
-			}
-		}
-
-		$this->scope = $this->scope->parent;
-		$this->popEnv();
-	}
-
-	protected function mediaParent($scope) {
-		while (!empty($scope->parent)) {
-			if (!empty($scope->type) && $scope->type != "media") {
-				break;
-			}
-			$scope = $scope->parent;
-		}
-
-		return $scope;
-	}
-
-	protected function compileNestedBlock($block, $selectors) {
-		$this->pushEnv($block);
-		$this->scope = $this->makeOutputBlock($block->type, $selectors);
-		$this->scope->parent->children[] = $this->scope;
-
-		$this->compileProps($block, $this->scope);
-
-		$this->scope = $this->scope->parent;
-		$this->popEnv();
-	}
-
-	protected function compileRoot($root) {
-		$this->pushEnv();
-		$this->scope = $this->makeOutputBlock($root->type);
-		$this->compileProps($root, $this->scope);
-		$this->popEnv();
-	}
-
-	protected function compileProps($block, $out) {
-		foreach ($this->sortProps($block->props) as $prop) {
-			$this->compileProp($prop, $block, $out);
-		}
-
-		$out->lines = array_values(array_unique($out->lines));
-	}
-
-	protected function sortProps($props, $split = false) {
-		$vars = array();
-		$imports = array();
-		$other = array();
-
-		foreach ($props as $prop) {
-			switch ($prop[0]) {
-			case "assign":
-				if (isset($prop[1][0]) && $prop[1][0] == $this->vPrefix) {
-					$vars[] = $prop;
-				} else {
-					$other[] = $prop;
-				}
-				break;
-			case "import":
-				$id = self::$nextImportId++;
-				$prop[] = $id;
-				$imports[] = $prop;
-				$other[] = array("import_mixin", $id);
-				break;
-			default:
-				$other[] = $prop;
-			}
-		}
-
-		if ($split) {
-			return array(array_merge($vars, $imports), $other);
-		} else {
-			return array_merge($vars, $imports, $other);
-		}
-	}
-
-	protected function compileMediaQuery($queries) {
-		$compiledQueries = array();
-		foreach ($queries as $query) {
-			$parts = array();
-			foreach ($query as $q) {
-				switch ($q[0]) {
-				case "mediaType":
-					$parts[] = implode(" ", array_slice($q, 1));
-					break;
-				case "mediaExp":
-					if (isset($q[2])) {
-						$parts[] = "($q[1]: " .
-							$this->compileValue($this->reduce($q[2])) . ")";
-					} else {
-						$parts[] = "($q[1])";
-					}
-					break;
-				case "variable":
-					$parts[] = $this->compileValue($this->reduce($q));
-				break;
-				}
-			}
-
-			if (count($parts) > 0) {
-				$compiledQueries[] =  implode(" and ", $parts);
-			}
-		}
-
-		$out = "@media";
-		if (!empty($parts)) {
-			$out .= " " .
-				implode($this->formatter->selectorSeparator, $compiledQueries);
-		}
-		return $out;
-	}
-
-	protected function multiplyMedia($env, $childQueries = null) {
-		if (is_null($env) ||
-			!empty($env->block->type) && $env->block->type != "media")
-		{
-			return $childQueries;
-		}
-
-		// plain old block, skip
-		if (empty($env->block->type)) {
-			return $this->multiplyMedia($env->parent, $childQueries);
-		}
-
-		$out = array();
-		$queries = $env->block->queries;
-		if (is_null($childQueries)) {
-			$out = $queries;
-		} else {
-			foreach ($queries as $parent) {
-				foreach ($childQueries as $child) {
-					$out[] = array_merge($parent, $child);
-				}
-			}
-		}
-
-		return $this->multiplyMedia($env->parent, $out);
-	}
-
-	protected function expandParentSelectors(&$tag, $replace) {
-		$parts = explode("$&$", $tag);
-		$count = 0;
-		foreach ($parts as &$part) {
-			$part = str_replace($this->parentSelector, $replace, $part, $c);
-			$count += $c;
-		}
-		$tag = implode($this->parentSelector, $parts);
-		return $count;
-	}
-
-	protected function findClosestSelectors() {
-		$env = $this->env;
-		$selectors = null;
-		while ($env !== null) {
-			if (isset($env->selectors)) {
-				$selectors = $env->selectors;
-				break;
-			}
-			$env = $env->parent;
-		}
-
-		return $selectors;
-	}
-
-
-	// multiply $selectors against the nearest selectors in env
-	protected function multiplySelectors($selectors) {
-		// find parent selectors
-
-		$parentSelectors = $this->findClosestSelectors();
-		if (is_null($parentSelectors)) {
-			// kill parent reference in top level selector
-			foreach ($selectors as &$s) {
-				$this->expandParentSelectors($s, "");
-			}
-
-			return $selectors;
-		}
-
-		$out = array();
-		foreach ($parentSelectors as $parent) {
-			foreach ($selectors as $child) {
-				$count = $this->expandParentSelectors($child, $parent);
-
-				// don't prepend the parent tag if & was used
-				if ($count > 0) {
-					$out[] = trim($child);
-				} else {
-					$out[] = trim($parent . ' ' . $child);
-				}
-			}
-		}
-
-		return $out;
-	}
-
-	// reduces selector expressions
-	protected function compileSelectors($selectors) {
-		$out = array();
-
-		foreach ($selectors as $s) {
-			if (is_array($s)) {
-				list(, $value) = $s;
-				$out[] = trim($this->compileValue($this->reduce($value)));
-			} else {
-				$out[] = $s;
-			}
-		}
-
-		return $out;
-	}
-
-	protected function eq($left, $right) {
-		return $left == $right;
-	}
-
-	protected function patternMatch($block, $orderedArgs, $keywordArgs) {
-		// match the guards if it has them
-		// any one of the groups must have all its guards pass for a match
-		if (!empty($block->guards)) {
-			$groupPassed = false;
-			foreach ($block->guards as $guardGroup) {
-				foreach ($guardGroup as $guard) {
-					$this->pushEnv();
-					$this->zipSetArgs($block->args, $orderedArgs, $keywordArgs);
-
-					$negate = false;
-					if ($guard[0] == "negate") {
-						$guard = $guard[1];
-						$negate = true;
-					}
-
-					$passed = $this->reduce($guard) == self::$TRUE;
-					if ($negate) $passed = !$passed;
-
-					$this->popEnv();
-
-					if ($passed) {
-						$groupPassed = true;
-					} else {
-						$groupPassed = false;
-						break;
-					}
-				}
-
-				if ($groupPassed) break;
-			}
-
-			if (!$groupPassed) {
-				return false;
-			}
-		}
-
-		if (empty($block->args)) {
-			return $block->isVararg || empty($orderedArgs) && empty($keywordArgs);
-		}
-
-		$remainingArgs = $block->args;
-		if ($keywordArgs) {
-			$remainingArgs = array();
-			foreach ($block->args as $arg) {
-				if ($arg[0] == "arg" && isset($keywordArgs[$arg[1]])) {
-					continue;
-				}
-
-				$remainingArgs[] = $arg;
-			}
-		}
-
-		$i = -1; // no args
-		// try to match by arity or by argument literal
-		foreach ($remainingArgs as $i => $arg) {
-			switch ($arg[0]) {
-			case "lit":
-				if (empty($orderedArgs[$i]) || !$this->eq($arg[1], $orderedArgs[$i])) {
-					return false;
-				}
-				break;
-			case "arg":
-				// no arg and no default value
-				if (!isset($orderedArgs[$i]) && !isset($arg[2])) {
-					return false;
-				}
-				break;
-			case "rest":
-				$i--; // rest can be empty
-				break 2;
-			}
-		}
-
-		if ($block->isVararg) {
-			return true; // not having enough is handled above
-		} else {
-			$numMatched = $i + 1;
-			// greater than becuase default values always match
-			return $numMatched >= count($orderedArgs);
-		}
-	}
-
-	protected function patternMatchAll($blocks, $orderedArgs, $keywordArgs, $skip=array()) {
-		$matches = null;
-		foreach ($blocks as $block) {
-			// skip seen blocks that don't have arguments
-			if (isset($skip[$block->id]) && !isset($block->args)) {
-				continue;
-			}
-
-			if ($this->patternMatch($block, $orderedArgs, $keywordArgs)) {
-				$matches[] = $block;
-			}
-		}
-
-		return $matches;
-	}
-
-	// attempt to find blocks matched by path and args
-	protected function findBlocks($searchIn, $path, $orderedArgs, $keywordArgs, $seen=array()) {
-		if ($searchIn == null) return null;
-		if (isset($seen[$searchIn->id])) return null;
-		$seen[$searchIn->id] = true;
-
-		$name = $path[0];
-
-		if (isset($searchIn->children[$name])) {
-			$blocks = $searchIn->children[$name];
-			if (count($path) == 1) {
-				$matches = $this->patternMatchAll($blocks, $orderedArgs, $keywordArgs, $seen);
-				if (!empty($matches)) {
-					// This will return all blocks that match in the closest
-					// scope that has any matching block, like lessjs
-					return $matches;
-				}
-			} else {
-				$matches = array();
-				foreach ($blocks as $subBlock) {
-					$subMatches = $this->findBlocks($subBlock,
-						array_slice($path, 1), $orderedArgs, $keywordArgs, $seen);
-
-					if (!is_null($subMatches)) {
-						foreach ($subMatches as $sm) {
-							$matches[] = $sm;
-						}
-					}
-				}
-
-				return count($matches) > 0 ? $matches : null;
-			}
-		}
-		if ($searchIn->parent === $searchIn) return null;
-		return $this->findBlocks($searchIn->parent, $path, $orderedArgs, $keywordArgs, $seen);
-	}
-
-	// sets all argument names in $args to either the default value
-	// or the one passed in through $values
-	protected function zipSetArgs($args, $orderedValues, $keywordValues) {
-		$assignedValues = array();
-
-		$i = 0;
-		foreach ($args as  $a) {
-			if ($a[0] == "arg") {
-				if (isset($keywordValues[$a[1]])) {
-					// has keyword arg
-					$value = $keywordValues[$a[1]];
-				} elseif (isset($orderedValues[$i])) {
-					// has ordered arg
-					$value = $orderedValues[$i];
-					$i++;
-				} elseif (isset($a[2])) {
-					// has default value
-					$value = $a[2];
-				} else {
-					$this->throwError("Failed to assign arg " . $a[1]);
-					$value = null; // :(
-				}
-
-				$value = $this->reduce($value);
-				$this->set($a[1], $value);
-				$assignedValues[] = $value;
-			} else {
-				// a lit
-				$i++;
-			}
-		}
-
-		// check for a rest
-		$last = end($args);
-		if ($last[0] == "rest") {
-			$rest = array_slice($orderedValues, count($args) - 1);
-			$this->set($last[1], $this->reduce(array("list", " ", $rest)));
-		}
-
-		// wow is this the only true use of PHP's + operator for arrays?
-		$this->env->arguments = $assignedValues + $orderedValues;
-	}
-
-	// compile a prop and update $lines or $blocks appropriately
-	protected function compileProp($prop, $block, $out) {
-		// set error position context
-		$this->sourceLoc = isset($prop[-1]) ? $prop[-1] : -1;
-
-		switch ($prop[0]) {
-		case 'assign':
-			list(, $name, $value) = $prop;
-			if ($name[0] == $this->vPrefix) {
-				$this->set($name, $value);
-			} else {
-				$out->lines[] = $this->formatter->property($name,
-						$this->compileValue($this->reduce($value)));
-			}
-			break;
-		case 'block':
-			list(, $child) = $prop;
-			$this->compileBlock($child);
-			break;
-		case 'mixin':
-			list(, $path, $args, $suffix) = $prop;
-
-			$orderedArgs = array();
-			$keywordArgs = array();
-			foreach ((array)$args as $arg) {
-				$argval = null;
-				switch ($arg[0]) {
-				case "arg":
-					if (!isset($arg[2])) {
-						$orderedArgs[] = $this->reduce(array("variable", $arg[1]));
-					} else {
-						$keywordArgs[$arg[1]] = $this->reduce($arg[2]);
-					}
-					break;
-
-				case "lit":
-					$orderedArgs[] = $this->reduce($arg[1]);
-					break;
-				default:
-					$this->throwError("Unknown arg type: " . $arg[0]);
-				}
-			}
-
-			$mixins = $this->findBlocks($block, $path, $orderedArgs, $keywordArgs);
-
-			if ($mixins === null) {
-				// fwrite(STDERR,"failed to find block: ".implode(" > ", $path)."\n");
-				break; // throw error here??
-			}
-
-			foreach ($mixins as $mixin) {
-				if ($mixin === $block && !$orderedArgs) {
-					continue;
-				}
-
-				$haveScope = false;
-				if (isset($mixin->parent->scope)) {
-					$haveScope = true;
-					$mixinParentEnv = $this->pushEnv();
-					$mixinParentEnv->storeParent = $mixin->parent->scope;
-				}
-
-				$haveArgs = false;
-				if (isset($mixin->args)) {
-					$haveArgs = true;
-					$this->pushEnv();
-					$this->zipSetArgs($mixin->args, $orderedArgs, $keywordArgs);
-				}
-
-				$oldParent = $mixin->parent;
-				if ($mixin != $block) $mixin->parent = $block;
-
-				foreach ($this->sortProps($mixin->props) as $subProp) {
-					if ($suffix !== null &&
-						$subProp[0] == "assign" &&
-						is_string($subProp[1]) &&
-						$subProp[1]{0} != $this->vPrefix)
-					{
-						$subProp[2] = array(
-							'list', ' ',
-							array($subProp[2], array('keyword', $suffix))
-						);
-					}
-
-					$this->compileProp($subProp, $mixin, $out);
-				}
-
-				$mixin->parent = $oldParent;
-
-				if ($haveArgs) $this->popEnv();
-				if ($haveScope) $this->popEnv();
-			}
-
-			break;
-		case 'raw':
-			$out->lines[] = $prop[1];
-			break;
-		case "directive":
-			list(, $name, $value) = $prop;
-			$out->lines[] = "@$name " . $this->compileValue($this->reduce($value)).';';
-			break;
-		case "comment":
-			$out->lines[] = $prop[1];
-			break;
-		case "import";
-			list(, $importPath, $importId) = $prop;
-			$importPath = $this->reduce($importPath);
-
-			if (!isset($this->env->imports)) {
-				$this->env->imports = array();
-			}
-
-			$result = $this->tryImport($importPath, $block, $out);
-
-			$this->env->imports[$importId] = $result === false ?
-				array(false, "@import " . $this->compileValue($importPath).";") :
-				$result;
-
-			break;
-		case "import_mixin":
-			list(,$importId) = $prop;
-			$import = $this->env->imports[$importId];
-			if ($import[0] === false) {
-				if (isset($import[1])) {
-					$out->lines[] = $import[1];
-				}
-			} else {
-				list(, $bottom, $parser, $importDir) = $import;
-				$this->compileImportedProps($bottom, $block, $out, $parser, $importDir);
-			}
-
-			break;
-		default:
-			$this->throwError("unknown op: {$prop[0]}\n");
-		}
-	}
-
-
-	/**
-	 * Compiles a primitive value into a CSS property value.
-	 *
-	 * Values in lessphp are typed by being wrapped in arrays, their format is
-	 * typically:
-	 *
-	 *     array(type, contents [, additional_contents]*)
-	 *
-	 * The input is expected to be reduced. This function will not work on
-	 * things like expressions and variables.
-	 */
-	protected function compileValue($value) {
-		switch ($value[0]) {
-		case 'list':
-			// [1] - delimiter
-			// [2] - array of values
-			return implode($value[1], array_map(array($this, 'compileValue'), $value[2]));
-		case 'raw_color':
-			if (!empty($this->formatter->compressColors)) {
-				return $this->compileValue($this->coerceColor($value));
-			}
-			return $value[1];
-		case 'keyword':
-			// [1] - the keyword
-			return $value[1];
-		case 'number':
-			list(, $num, $unit) = $value;
-			// [1] - the number
-			// [2] - the unit
-			if ($this->numberPrecision !== null) {
-				$num = round($num, $this->numberPrecision);
-			}
-			return $num . $unit;
-		case 'string':
-			// [1] - contents of string (includes quotes)
-			list(, $delim, $content) = $value;
-			foreach ($content as &$part) {
-				if (is_array($part)) {
-					$part = $this->compileValue($part);
-				}
-			}
-			return $delim . implode($content) . $delim;
-		case 'color':
-			// [1] - red component (either number or a %)
-			// [2] - green component
-			// [3] - blue component
-			// [4] - optional alpha component
-			list(, $r, $g, $b) = $value;
-			$r = round($r);
-			$g = round($g);
-			$b = round($b);
-
-			if (count($value) == 5 && $value[4] != 1) { // rgba
-				return 'rgba('.$r.','.$g.','.$b.','.$value[4].')';
-			}
-
-			$h = sprintf("#%02x%02x%02x", $r, $g, $b);
-
-			if (!empty($this->formatter->compressColors)) {
-				// Converting hex color to short notation (e.g. #003399 to #039)
-				if ($h[1] === $h[2] && $h[3] === $h[4] && $h[5] === $h[6]) {
-					$h = '#' . $h[1] . $h[3] . $h[5];
-				}
-			}
-
-			return $h;
-
-		case 'function':
-			list(, $name, $args) = $value;
-			return $name.'('.$this->compileValue($args).')';
-		default: // assumed to be unit
-			$this->throwError("unknown value type: $value[0]");
-		}
-	}
-
-	protected function lib_pow($args) {
-		list($base, $exp) = $this->assertArgs($args, 2, "pow");
-		return pow($this->assertNumber($base), $this->assertNumber($exp));
-	}
-
-	protected function lib_pi() {
-		return pi();
-	}
-
-	protected function lib_mod($args) {
-		list($a, $b) = $this->assertArgs($args, 2, "mod");
-		return $this->assertNumber($a) % $this->assertNumber($b);
-	}
-
-	protected function lib_tan($num) {
-		return tan($this->assertNumber($num));
-	}
-
-	protected function lib_sin($num) {
-		return sin($this->assertNumber($num));
-	}
-
-	protected function lib_cos($num) {
-		return cos($this->assertNumber($num));
-	}
-
-	protected function lib_atan($num) {
-		$num = atan($this->assertNumber($num));
-		return array("number", $num, "rad");
-	}
-
-	protected function lib_asin($num) {
-		$num = asin($this->assertNumber($num));
-		return array("number", $num, "rad");
-	}
-
-	protected function lib_acos($num) {
-		$num = acos($this->assertNumber($num));
-		return array("number", $num, "rad");
-	}
-
-	protected function lib_sqrt($num) {
-		return sqrt($this->assertNumber($num));
-	}
-
-	protected function lib_extract($value) {
-		list($list, $idx) = $this->assertArgs($value, 2, "extract");
-		$idx = $this->assertNumber($idx);
-		// 1 indexed
-		if ($list[0] == "list" && isset($list[2][$idx - 1])) {
-			return $list[2][$idx - 1];
-		}
-	}
-
-	protected function lib_isnumber($value) {
-		return $this->toBool($value[0] == "number");
-	}
-
-	protected function lib_isstring($value) {
-		return $this->toBool($value[0] == "string");
-	}
-
-	protected function lib_iscolor($value) {
-		return $this->toBool($this->coerceColor($value));
-	}
-
-	protected function lib_iskeyword($value) {
-		return $this->toBool($value[0] == "keyword");
-	}
-
-	protected function lib_ispixel($value) {
-		return $this->toBool($value[0] == "number" && $value[2] == "px");
-	}
-
-	protected function lib_ispercentage($value) {
-		return $this->toBool($value[0] == "number" && $value[2] == "%");
-	}
-
-	protected function lib_isem($value) {
-		return $this->toBool($value[0] == "number" && $value[2] == "em");
-	}
-
-	protected function lib_isrem($value) {
-		return $this->toBool($value[0] == "number" && $value[2] == "rem");
-	}
-
-	protected function lib_rgbahex($color) {
-		$color = $this->coerceColor($color);
-		if (is_null($color))
-			$this->throwError("color expected for rgbahex");
-
-		return sprintf("#%02x%02x%02x%02x",
-			isset($color[4]) ? $color[4]*255 : 255,
-			$color[1],$color[2], $color[3]);
-	}
-
-	protected function lib_argb($color){
-		return $this->lib_rgbahex($color);
-	}
-
-	// utility func to unquote a string
-	protected function lib_e($arg) {
-		switch ($arg[0]) {
-			case "list":
-				$items = $arg[2];
-				if (isset($items[0])) {
-					return $this->lib_e($items[0]);
-				}
-				return self::$defaultValue;
-			case "string":
-				$arg[1] = "";
-				return $arg;
-			case "keyword":
-				return $arg;
-			default:
-				return array("keyword", $this->compileValue($arg));
-		}
-	}
-
-	protected function lib__sprintf($args) {
-		if ($args[0] != "list") return $args;
-		$values = $args[2];
-		$string = array_shift($values);
-		$template = $this->compileValue($this->lib_e($string));
-
-		$i = 0;
-		if (preg_match_all('/%[dsa]/', $template, $m)) {
-			foreach ($m[0] as $match) {
-				$val = isset($values[$i]) ?
-					$this->reduce($values[$i]) : array('keyword', '');
-
-				// lessjs compat, renders fully expanded color, not raw color
-				if ($color = $this->coerceColor($val)) {
-					$val = $color;
-				}
-
-				$i++;
-				$rep = $this->compileValue($this->lib_e($val));
-				$template = preg_replace('/'.self::preg_quote($match).'/',
-					$rep, $template, 1);
-			}
-		}
-
-		$d = $string[0] == "string" ? $string[1] : '"';
-		return array("string", $d, array($template));
-	}
-
-	protected function lib_floor($arg) {
-		$value = $this->assertNumber($arg);
-		return array("number", floor($value), $arg[2]);
-	}
-
-	protected function lib_ceil($arg) {
-		$value = $this->assertNumber($arg);
-		return array("number", ceil($value), $arg[2]);
-	}
-
-	protected function lib_round($arg) {
-		$value = $this->assertNumber($arg);
-		return array("number", round($value), $arg[2]);
-	}
-
-	protected function lib_unit($arg) {
-		if ($arg[0] == "list") {
-			list($number, $newUnit) = $arg[2];
-			return array("number", $this->assertNumber($number),
-				$this->compileValue($this->lib_e($newUnit)));
-		} else {
-			return array("number", $this->assertNumber($arg), "");
-		}
-	}
-
-	/**
-	 * Helper function to get arguments for color manipulation functions.
-	 * takes a list that contains a color like thing and a percentage
-	 */
-	protected function colorArgs($args) {
-		if ($args[0] != 'list' || count($args[2]) < 2) {
-			return array(array('color', 0, 0, 0), 0);
-		}
-		list($color, $delta) = $args[2];
-		$color = $this->assertColor($color);
-		$delta = floatval($delta[1]);
-
-		return array($color, $delta);
-	}
-
-	protected function lib_darken($args) {
-		list($color, $delta) = $this->colorArgs($args);
-
-		$hsl = $this->toHSL($color);
-		$hsl[3] = $this->clamp($hsl[3] - $delta, 100);
-		return $this->toRGB($hsl);
-	}
-
-	protected function lib_lighten($args) {
-		list($color, $delta) = $this->colorArgs($args);
-
-		$hsl = $this->toHSL($color);
-		$hsl[3] = $this->clamp($hsl[3] + $delta, 100);
-		return $this->toRGB($hsl);
-	}
-
-	protected function lib_saturate($args) {
-		list($color, $delta) = $this->colorArgs($args);
-
-		$hsl = $this->toHSL($color);
-		$hsl[2] = $this->clamp($hsl[2] + $delta, 100);
-		return $this->toRGB($hsl);
-	}
-
-	protected function lib_desaturate($args) {
-		list($color, $delta) = $this->colorArgs($args);
-
-		$hsl = $this->toHSL($color);
-		$hsl[2] = $this->clamp($hsl[2] - $delta, 100);
-		return $this->toRGB($hsl);
-	}
-
-	protected function lib_spin($args) {
-		list($color, $delta) = $this->colorArgs($args);
-
-		$hsl = $this->toHSL($color);
-
-		$hsl[1] = $hsl[1] + $delta % 360;
-		if ($hsl[1] < 0) $hsl[1] += 360;
-
-		return $this->toRGB($hsl);
-	}
-
-	protected function lib_fadeout($args) {
-		list($color, $delta) = $this->colorArgs($args);
-		$color[4] = $this->clamp((isset($color[4]) ? $color[4] : 1) - $delta/100);
-		return $color;
-	}
-
-	protected function lib_fadein($args) {
-		list($color, $delta) = $this->colorArgs($args);
-		$color[4] = $this->clamp((isset($color[4]) ? $color[4] : 1) + $delta/100);
-		return $color;
-	}
-
-	protected function lib_hue($color) {
-		$hsl = $this->toHSL($this->assertColor($color));
-		return round($hsl[1]);
-	}
-
-	protected function lib_saturation($color) {
-		$hsl = $this->toHSL($this->assertColor($color));
-		return round($hsl[2]);
-	}
-
-	protected function lib_lightness($color) {
-		$hsl = $this->toHSL($this->assertColor($color));
-		return round($hsl[3]);
-	}
-
-	// get the alpha of a color
-	// defaults to 1 for non-colors or colors without an alpha
-	protected function lib_alpha($value) {
-		if (!is_null($color = $this->coerceColor($value))) {
-			return isset($color[4]) ? $color[4] : 1;
-		}
-	}
-
-	// set the alpha of the color
-	protected function lib_fade($args) {
-		list($color, $alpha) = $this->colorArgs($args);
-		$color[4] = $this->clamp($alpha / 100.0);
-		return $color;
-	}
-
-	protected function lib_percentage($arg) {
-		$num = $this->assertNumber($arg);
-		return array("number", $num*100, "%");
-	}
-
-	// mixes two colors by weight
-	// mix(@color1, @color2, [@weight: 50%]);
-	// http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#mix-instance_method
-	protected function lib_mix($args) {
-		if ($args[0] != "list" || count($args[2]) < 2)
-			$this->throwError("mix expects (color1, color2, weight)");
-
-		list($first, $second) = $args[2];
-		$first = $this->assertColor($first);
-		$second = $this->assertColor($second);
-
-		$first_a = $this->lib_alpha($first);
-		$second_a = $this->lib_alpha($second);
-
-		if (isset($args[2][2])) {
-			$weight = $args[2][2][1] / 100.0;
-		} else {
-			$weight = 0.5;
-		}
-
-		$w = $weight * 2 - 1;
-		$a = $first_a - $second_a;
-
-		$w1 = (($w * $a == -1 ? $w : ($w + $a)/(1 + $w * $a)) + 1) / 2.0;
-		$w2 = 1.0 - $w1;
-
-		$new = array('color',
-			$w1 * $first[1] + $w2 * $second[1],
-			$w1 * $first[2] + $w2 * $second[2],
-			$w1 * $first[3] + $w2 * $second[3],
-		);
-
-		if ($first_a != 1.0 || $second_a != 1.0) {
-			$new[] = $first_a * $weight + $second_a * ($weight - 1);
-		}
-
-		return $this->fixColor($new);
-	}
-
-	protected function lib_contrast($args) {
-		if ($args[0] != 'list' || count($args[2]) < 3) {
-			return array(array('color', 0, 0, 0), 0);
-		}
-
-		list($inputColor, $darkColor, $lightColor) = $args[2];
-
-		$inputColor = $this->assertColor($inputColor);
-		$darkColor = $this->assertColor($darkColor);
-		$lightColor = $this->assertColor($lightColor);
-		$hsl = $this->toHSL($inputColor);
-
-		if ($hsl[3] > 50) {
-			return $darkColor;
-		}
-
-		return $lightColor;
-	}
-
-	protected function assertColor($value, $error = "expected color value") {
-		$color = $this->coerceColor($value);
-		if (is_null($color)) $this->throwError($error);
-		return $color;
-	}
-
-	protected function assertNumber($value, $error = "expecting number") {
-		if ($value[0] == "number") return $value[1];
-		$this->throwError($error);
-	}
-
-	protected function assertArgs($value, $expectedArgs, $name="") {
-		if ($expectedArgs == 1) {
-			return $value;
-		} else {
-			if ($value[0] !== "list" || $value[1] != ",") $this->throwError("expecting list");
-			$values = $value[2];
-			$numValues = count($values);
-			if ($expectedArgs != $numValues) {
-				if ($name) {
-					$name = $name . ": ";
-				}
-
-				$this->throwError("${name}expecting $expectedArgs arguments, got $numValues");
-			}
-
-			return $values;
-		}
-	}
-
-	protected function toHSL($color) {
-		if ($color[0] == 'hsl') return $color;
-
-		$r = $color[1] / 255;
-		$g = $color[2] / 255;
-		$b = $color[3] / 255;
-
-		$min = min($r, $g, $b);
-		$max = max($r, $g, $b);
-
-		$L = ($min + $max) / 2;
-		if ($min == $max) {
-			$S = $H = 0;
-		} else {
-			if ($L < 0.5)
-				$S = ($max - $min)/($max + $min);
-			else
-				$S = ($max - $min)/(2.0 - $max - $min);
-
-			if ($r == $max) $H = ($g - $b)/($max - $min);
-			elseif ($g == $max) $H = 2.0 + ($b - $r)/($max - $min);
-			elseif ($b == $max) $H = 4.0 + ($r - $g)/($max - $min);
-
-		}
-
-		$out = array('hsl',
-			($H < 0 ? $H + 6 : $H)*60,
-			$S*100,
-			$L*100,
-		);
-
-		if (count($color) > 4) $out[] = $color[4]; // copy alpha
-		return $out;
-	}
-
-	protected function toRGB_helper($comp, $temp1, $temp2) {
-		if ($comp < 0) $comp += 1.0;
-		elseif ($comp > 1) $comp -= 1.0;
-
-		if (6 * $comp < 1) return $temp1 + ($temp2 - $temp1) * 6 * $comp;
-		if (2 * $comp < 1) return $temp2;
-		if (3 * $comp < 2) return $temp1 + ($temp2 - $temp1)*((2/3) - $comp) * 6;
-
-		return $temp1;
-	}
-
-	/**
-	 * Converts a hsl array into a color value in rgb.
-	 * Expects H to be in range of 0 to 360, S and L in 0 to 100
-	 */
-	protected function toRGB($color) {
-		if ($color[0] == 'color') return $color;
-
-		$H = $color[1] / 360;
-		$S = $color[2] / 100;
-		$L = $color[3] / 100;
-
-		if ($S == 0) {
-			$r = $g = $b = $L;
-		} else {
-			$temp2 = $L < 0.5 ?
-				$L*(1.0 + $S) :
-				$L + $S - $L * $S;
-
-			$temp1 = 2.0 * $L - $temp2;
-
-			$r = $this->toRGB_helper($H + 1/3, $temp1, $temp2);
-			$g = $this->toRGB_helper($H, $temp1, $temp2);
-			$b = $this->toRGB_helper($H - 1/3, $temp1, $temp2);
-		}
-
-		// $out = array('color', round($r*255), round($g*255), round($b*255));
-		$out = array('color', $r*255, $g*255, $b*255);
-		if (count($color) > 4) $out[] = $color[4]; // copy alpha
-		return $out;
-	}
-
-	protected function clamp($v, $max = 1, $min = 0) {
-		return min($max, max($min, $v));
-	}
-
-	/**
-	 * Convert the rgb, rgba, hsl color literals of function type
-	 * as returned by the parser into values of color type.
-	 */
-	protected function funcToColor($func) {
-		$fname = $func[1];
-		if ($func[2][0] != 'list') return false; // need a list of arguments
-		$rawComponents = $func[2][2];
-
-		if ($fname == 'hsl' || $fname == 'hsla') {
-			$hsl = array('hsl');
-			$i = 0;
-			foreach ($rawComponents as $c) {
-				$val = $this->reduce($c);
-				$val = isset($val[1]) ? floatval($val[1]) : 0;
-
-				if ($i == 0) $clamp = 360;
-				elseif ($i < 3) $clamp = 100;
-				else $clamp = 1;
-
-				$hsl[] = $this->clamp($val, $clamp);
-				$i++;
-			}
-
-			while (count($hsl) < 4) $hsl[] = 0;
-			return $this->toRGB($hsl);
-
-		} elseif ($fname == 'rgb' || $fname == 'rgba') {
-			$components = array();
-			$i = 1;
-			foreach	($rawComponents as $c) {
-				$c = $this->reduce($c);
-				if ($i < 4) {
-					if ($c[0] == "number" && $c[2] == "%") {
-						$components[] = 255 * ($c[1] / 100);
-					} else {
-						$components[] = floatval($c[1]);
-					}
-				} elseif ($i == 4) {
-					if ($c[0] == "number" && $c[2] == "%") {
-						$components[] = 1.0 * ($c[1] / 100);
-					} else {
-						$components[] = floatval($c[1]);
-					}
-				} else break;
-
-				$i++;
-			}
-			while (count($components) < 3) $components[] = 0;
-			array_unshift($components, 'color');
-			return $this->fixColor($components);
-		}
-
-		return false;
-	}
-
-	protected function reduce($value, $forExpression = false) {
-		switch ($value[0]) {
-		case "interpolate":
-			$reduced = $this->reduce($value[1]);
-			$var = $this->compileValue($reduced);
-			$res = $this->reduce(array("variable", $this->vPrefix . $var));
-
-			if ($res[0] == "raw_color") {
-				$res = $this->coerceColor($res);
-			}
-
-			if (empty($value[2])) $res = $this->lib_e($res);
-
-			return $res;
-		case "variable":
-			$key = $value[1];
-			if (is_array($key)) {
-				$key = $this->reduce($key);
-				$key = $this->vPrefix . $this->compileValue($this->lib_e($key));
-			}
-
-			$seen =& $this->env->seenNames;
-
-			if (!empty($seen[$key])) {
-				$this->throwError("infinite loop detected: $key");
-			}
-
-			$seen[$key] = true;
-			$out = $this->reduce($this->get($key, self::$defaultValue));
-			$seen[$key] = false;
-			return $out;
-		case "list":
-			foreach ($value[2] as &$item) {
-				$item = $this->reduce($item, $forExpression);
-			}
-			return $value;
-		case "expression":
-			return $this->evaluate($value);
-		case "string":
-			foreach ($value[2] as &$part) {
-				if (is_array($part)) {
-					$strip = $part[0] == "variable";
-					$part = $this->reduce($part);
-					if ($strip) $part = $this->lib_e($part);
-				}
-			}
-			return $value;
-		case "escape":
-			list(,$inner) = $value;
-			return $this->lib_e($this->reduce($inner));
-		case "function":
-			$color = $this->funcToColor($value);
-			if ($color) return $color;
-
-			list(, $name, $args) = $value;
-			if ($name == "%") $name = "_sprintf";
-			$f = isset($this->libFunctions[$name]) ?
-				$this->libFunctions[$name] : array($this, 'lib_'.$name);
-
-			if (is_callable($f)) {
-				if ($args[0] == 'list')
-					$args = self::compressList($args[2], $args[1]);
-
-				$ret = call_user_func($f, $this->reduce($args, true), $this);
-
-				if (is_null($ret)) {
-					return array("string", "", array(
-						$name, "(", $args, ")"
-					));
-				}
-
-				// convert to a typed value if the result is a php primitive
-				if (is_numeric($ret)) $ret = array('number', $ret, "");
-				elseif (!is_array($ret)) $ret = array('keyword', $ret);
-
-				return $ret;
-			}
-
-			// plain function, reduce args
-			$value[2] = $this->reduce($value[2]);
-			return $value;
-		case "unary":
-			list(, $op, $exp) = $value;
-			$exp = $this->reduce($exp);
-
-			if ($exp[0] == "number") {
-				switch ($op) {
-				case "+":
-					return $exp;
-				case "-":
-					$exp[1] *= -1;
-					return $exp;
-				}
-			}
-			return array("string", "", array($op, $exp));
-		}
-
-		if ($forExpression) {
-			switch ($value[0]) {
-			case "keyword":
-				if ($color = $this->coerceColor($value)) {
-					return $color;
-				}
-				break;
-			case "raw_color":
-				return $this->coerceColor($value);
-			}
-		}
-
-		return $value;
-	}
-
-
-	// coerce a value for use in color operation
-	protected function coerceColor($value) {
-		switch($value[0]) {
-			case 'color': return $value;
-			case 'raw_color':
-				$c = array("color", 0, 0, 0);
-				$colorStr = substr($value[1], 1);
-				$num = hexdec($colorStr);
-				$width = strlen($colorStr) == 3 ? 16 : 256;
-
-				for ($i = 3; $i > 0; $i--) { // 3 2 1
-					$t = $num % $width;
-					$num /= $width;
-
-					$c[$i] = $t * (256/$width) + $t * floor(16/$width);
-				}
-
-				return $c;
-			case 'keyword':
-				$name = $value[1];
-				if (isset(self::$cssColors[$name])) {
-					$rgba = explode(',', self::$cssColors[$name]);
-
-					if(isset($rgba[3]))
-						return array('color', $rgba[0], $rgba[1], $rgba[2], $rgba[3]);
-
-					return array('color', $rgba[0], $rgba[1], $rgba[2]);
-				}
-				return null;
-		}
-	}
-
-	// make something string like into a string
-	protected function coerceString($value) {
-		switch ($value[0]) {
-		case "string":
-			return $value;
-		case "keyword":
-			return array("string", "", array($value[1]));
-		}
-		return null;
-	}
-
-	// turn list of length 1 into value type
-	protected function flattenList($value) {
-		if ($value[0] == "list" && count($value[2]) == 1) {
-			return $this->flattenList($value[2][0]);
-		}
-		return $value;
-	}
-
-	protected function toBool($a) {
-		if ($a) return self::$TRUE;
-		else return self::$FALSE;
-	}
-
-	// evaluate an expression
-	protected function evaluate($exp) {
-		list(, $op, $left, $right, $whiteBefore, $whiteAfter) = $exp;
-
-		$left = $this->reduce($left, true);
-		$right = $this->reduce($right, true);
-
-		if ($leftColor = $this->coerceColor($left)) {
-			$left = $leftColor;
-		}
-
-		if ($rightColor = $this->coerceColor($right)) {
-			$right = $rightColor;
-		}
-
-		$ltype = $left[0];
-		$rtype = $right[0];
-
-		// operators that work on all types
-		if ($op == "and") {
-			return $this->toBool($left == self::$TRUE && $right == self::$TRUE);
-		}
-
-		if ($op == "=") {
-			return $this->toBool($this->eq($left, $right) );
-		}
-
-		if ($op == "+" && !is_null($str = $this->stringConcatenate($left, $right))) {
-			return $str;
-		}
-
-		// type based operators
-		$fname = "op_${ltype}_${rtype}";
-		if (is_callable(array($this, $fname))) {
-			$out = $this->$fname($op, $left, $right);
-			if (!is_null($out)) return $out;
-		}
-
-		// make the expression look it did before being parsed
-		$paddedOp = $op;
-		if ($whiteBefore) $paddedOp = " " . $paddedOp;
-		if ($whiteAfter) $paddedOp .= " ";
-
-		return array("string", "", array($left, $paddedOp, $right));
-	}
-
-	protected function stringConcatenate($left, $right) {
-		if ($strLeft = $this->coerceString($left)) {
-			if ($right[0] == "string") {
-				$right[1] = "";
-			}
-			$strLeft[2][] = $right;
-			return $strLeft;
-		}
-
-		if ($strRight = $this->coerceString($right)) {
-			array_unshift($strRight[2], $left);
-			return $strRight;
-		}
-	}
-
-
-	// make sure a color's components don't go out of bounds
-	protected function fixColor($c) {
-		foreach (range(1, 3) as $i) {
-			if ($c[$i] < 0) $c[$i] = 0;
-			if ($c[$i] > 255) $c[$i] = 255;
-		}
-
-		return $c;
-	}
-
-	protected function op_number_color($op, $lft, $rgt) {
-		if ($op == '+' || $op == '*') {
-			return $this->op_color_number($op, $rgt, $lft);
-		}
-	}
-
-	protected function op_color_number($op, $lft, $rgt) {
-		if ($rgt[0] == '%') $rgt[1] /= 100;
-
-		return $this->op_color_color($op, $lft,
-			array_fill(1, count($lft) - 1, $rgt[1]));
-	}
-
-	protected function op_color_color($op, $left, $right) {
-		$out = array('color');
-		$max = count($left) > count($right) ? count($left) : count($right);
-		foreach (range(1, $max - 1) as $i) {
-			$lval = isset($left[$i]) ? $left[$i] : 0;
-			$rval = isset($right[$i]) ? $right[$i] : 0;
-			switch ($op) {
-			case '+':
-				$out[] = $lval + $rval;
-				break;
-			case '-':
-				$out[] = $lval - $rval;
-				break;
-			case '*':
-				$out[] = $lval * $rval;
-				break;
-			case '%':
-				$out[] = $lval % $rval;
-				break;
-			case '/':
-				if ($rval == 0) $this->throwError("evaluate error: can't divide by zero");
-				$out[] = $lval / $rval;
-				break;
-			default:
-				$this->throwError('evaluate error: color op number failed on op '.$op);
-			}
-		}
-		return $this->fixColor($out);
-	}
-
-	function lib_red($color){
-		$color = $this->coerceColor($color);
-		if (is_null($color)) {
-			$this->throwError('color expected for red()');
-		}
-
-		return $color[1];
-	}
-
-	function lib_green($color){
-		$color = $this->coerceColor($color);
-		if (is_null($color)) {
-			$this->throwError('color expected for green()');
-		}
-
-		return $color[2];
-	}
-
-	function lib_blue($color){
-		$color = $this->coerceColor($color);
-		if (is_null($color)) {
-			$this->throwError('color expected for blue()');
-		}
-
-		return $color[3];
-	}
-
-
-	// operator on two numbers
-	protected function op_number_number($op, $left, $right) {
-		$unit = empty($left[2]) ? $right[2] : $left[2];
-
-		$value = 0;
-		switch ($op) {
-		case '+':
-			$value = $left[1] + $right[1];
-			break;
-		case '*':
-			$value = $left[1] * $right[1];
-			break;
-		case '-':
-			$value = $left[1] - $right[1];
-			break;
-		case '%':
-			$value = $left[1] % $right[1];
-			break;
-		case '/':
-			if ($right[1] == 0) $this->throwError('parse error: divide by zero');
-			$value = $left[1] / $right[1];
-			break;
-		case '<':
-			return $this->toBool($left[1] < $right[1]);
-		case '>':
-			return $this->toBool($left[1] > $right[1]);
-		case '>=':
-			return $this->toBool($left[1] >= $right[1]);
-		case '=<':
-			return $this->toBool($left[1] <= $right[1]);
-		default:
-			$this->throwError('parse error: unknown number operator: '.$op);
-		}
-
-		return array("number", $value, $unit);
-	}
-
-
-	/* environment functions */
-
-	protected function makeOutputBlock($type, $selectors = null) {
-		$b = new stdclass;
-		$b->lines = array();
-		$b->children = array();
-		$b->selectors = $selectors;
-		$b->type = $type;
-		$b->parent = $this->scope;
-		return $b;
-	}
-
-	// the state of execution
-	protected function pushEnv($block = null) {
-		$e = new stdclass;
-		$e->parent = $this->env;
-		$e->store = array();
-		$e->block = $block;
-
-		$this->env = $e;
-		return $e;
-	}
-
-	// pop something off the stack
-	protected function popEnv() {
-		$old = $this->env;
-		$this->env = $this->env->parent;
-		return $old;
-	}
-
-	// set something in the current env
-	protected function set($name, $value) {
-		$this->env->store[$name] = $value;
-	}
-
-
-	// get the highest occurrence entry for a name
-	protected function get($name, $default=null) {
-		$current = $this->env;
-
-		$isArguments = $name == $this->vPrefix . 'arguments';
-		while ($current) {
-			if ($isArguments && isset($current->arguments)) {
-				return array('list', ' ', $current->arguments);
-			}
-
-			if (isset($current->store[$name]))
-				return $current->store[$name];
-			else {
-				$current = isset($current->storeParent) ?
-					$current->storeParent : $current->parent;
-			}
-		}
-
-		return $default;
-	}
-
-	// inject array of unparsed strings into environment as variables
-	protected function injectVariables($args) {
-		$this->pushEnv();
-		$parser = new lessc_parser($this, __METHOD__);
-		foreach ($args as $name => $strValue) {
-			if ($name{0} != '@') $name = '@'.$name;
-			$parser->count = 0;
-			$parser->buffer = (string)$strValue;
-			if (!$parser->propertyValue($value)) {
-				throw new Exception("failed to parse passed in variable $name: $strValue");
-			}
-
-			$this->set($name, $value);
-		}
-	}
-
-	/**
-	 * Initialize any static state, can initialize parser for a file
-	 * $opts isn't used yet
-	 */
-	public function __construct($fname = null) {
-		if ($fname !== null) {
-			// used for deprecated parse method
-			$this->_parseFile = $fname;
-		}
-	}
-
-	public function compile($string, $name = null) {
-		$locale = setlocale(LC_NUMERIC, 0);
-		setlocale(LC_NUMERIC, "C");
-
-		$this->parser = $this->makeParser($name);
-		$root = $this->parser->parse($string);
-
-		$this->env = null;
-		$this->scope = null;
-
-		$this->formatter = $this->newFormatter();
-
-		if (!empty($this->registeredVars)) {
-			$this->injectVariables($this->registeredVars);
-		}
-
-		$this->sourceParser = $this->parser; // used for error messages
-		$this->compileBlock($root);
-
-		ob_start();
-		$this->formatter->block($this->scope);
-		$out = ob_get_clean();
-		setlocale(LC_NUMERIC, $locale);
-		return $out;
-	}
-
-	public function compileFile($fname, $outFname = null) {
-		if (!is_readable($fname)) {
-			throw new Exception('load error: failed to find '.$fname);
-		}
-
-		$pi = pathinfo($fname);
-
-		$oldImport = $this->importDir;
-
-		$this->importDir = (array)$this->importDir;
-		$this->importDir[] = $pi['dirname'].'/';
-
-		$this->addParsedFile($fname);
-
-		$out = $this->compile(file_get_contents($fname), $fname);
-
-		$this->importDir = $oldImport;
-
-		if ($outFname !== null) {
-			return file_put_contents($outFname, $out);
-		}
-
-		return $out;
-	}
-
-	// compile only if changed input has changed or output doesn't exist
-	public function checkedCompile($in, $out) {
-		if (!is_file($out) || filemtime($in) > filemtime($out)) {
-			$this->compileFile($in, $out);
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	 * Execute lessphp on a .less file or a lessphp cache structure
-	 *
-	 * The lessphp cache structure contains information about a specific
-	 * less file having been parsed. It can be used as a hint for future
-	 * calls to determine whether or not a rebuild is required.
-	 *
-	 * The cache structure contains two important keys that may be used
-	 * externally:
-	 *
-	 * compiled: The final compiled CSS
-	 * updated: The time (in seconds) the CSS was last compiled
-	 *
-	 * The cache structure is a plain-ol' PHP associative array and can
-	 * be serialized and unserialized without a hitch.
-	 *
-	 * @param mixed $in Input
-	 * @param bool $force Force rebuild?
-	 * @return array lessphp cache structure
-	 */
-	public function cachedCompile($in, $force = false) {
-		// assume no root
-		$root = null;
-
-		if (is_string($in)) {
-			$root = $in;
-		} elseif (is_array($in) and isset($in['root'])) {
-			if ($force or ! isset($in['files'])) {
-				// If we are forcing a recompile or if for some reason the
-				// structure does not contain any file information we should
-				// specify the root to trigger a rebuild.
-				$root = $in['root'];
-			} elseif (isset($in['files']) and is_array($in['files'])) {
-				foreach ($in['files'] as $fname => $ftime ) {
-					if (!file_exists($fname) or filemtime($fname) > $ftime) {
-						// One of the files we knew about previously has changed
-						// so we should look at our incoming root again.
-						$root = $in['root'];
-						break;
-					}
-				}
-			}
-		} else {
-			// TODO: Throw an exception? We got neither a string nor something
-			// that looks like a compatible lessphp cache structure.
-			return null;
-		}
-
-		if ($root !== null) {
-			// If we have a root value which means we should rebuild.
-			$out = array();
-			$out['root'] = $root;
-			$out['compiled'] = $this->compileFile($root);
-			$out['files'] = $this->allParsedFiles();
-			$out['updated'] = time();
-			return $out;
-		} else {
-			// No changes, pass back the structure
-			// we were given initially.
-			return $in;
-		}
-
-	}
-
-	// parse and compile buffer
-	// This is deprecated
-	public function parse($str = null, $initialVariables = null) {
-		if (is_array($str)) {
-			$initialVariables = $str;
-			$str = null;
-		}
-
-		$oldVars = $this->registeredVars;
-		if ($initialVariables !== null) {
-			$this->setVariables($initialVariables);
-		}
-
-		if ($str == null) {
-			if (empty($this->_parseFile)) {
-				throw new exception("nothing to parse");
-			}
-
-			$out = $this->compileFile($this->_parseFile);
-		} else {
-			$out = $this->compile($str);
-		}
-
-		$this->registeredVars = $oldVars;
-		return $out;
-	}
-
-	protected function makeParser($name) {
-		$parser = new lessc_parser($this, $name);
-		$parser->writeComments = $this->preserveComments;
-
-		return $parser;
-	}
-
-	public function setFormatter($name) {
-		$this->formatterName = $name;
-	}
-
-	protected function newFormatter() {
-		$className = "lessc_formatter_lessjs";
-		if (!empty($this->formatterName)) {
-			if (!is_string($this->formatterName))
-				return $this->formatterName;
-			$className = "lessc_formatter_$this->formatterName";
-		}
-
-		return new $className;
-	}
-
-	public function setPreserveComments($preserve) {
-		$this->preserveComments = $preserve;
-	}
-
-	public function registerFunction($name, $func) {
-		$this->libFunctions[$name] = $func;
-	}
-
-	public function unregisterFunction($name) {
-		unset($this->libFunctions[$name]);
-	}
-
-	public function setVariables($variables) {
-		$this->registeredVars = array_merge($this->registeredVars, $variables);
-	}
-
-	public function unsetVariable($name) {
-		unset($this->registeredVars[$name]);
-	}
-
-	public function setImportDir($dirs) {
-		$this->importDir = (array)$dirs;
-	}
-
-	public function addImportDir($dir) {
-		$this->importDir = (array)$this->importDir;
-		$this->importDir[] = $dir;
-	}
-
-	public function allParsedFiles() {
-		return $this->allParsedFiles;
-	}
-
-	protected function addParsedFile($file) {
-		$this->allParsedFiles[realpath($file)] = filemtime($file);
-	}
-
-	/**
-	 * Uses the current value of $this->count to show line and line number
-	 */
-	protected function throwError($msg = null) {
-		if ($this->sourceLoc >= 0) {
-			$this->sourceParser->throwError($msg, $this->sourceLoc);
-		}
-		throw new exception($msg);
-	}
-
-	// compile file $in to file $out if $in is newer than $out
-	// returns true when it compiles, false otherwise
-	public static function ccompile($in, $out, $less = null) {
-		if ($less === null) {
-			$less = new self;
-		}
-		return $less->checkedCompile($in, $out);
-	}
-
-	public static function cexecute($in, $force = false, $less = null) {
-		if ($less === null) {
-			$less = new self;
-		}
-		return $less->cachedCompile($in, $force);
-	}
-
-	static protected $cssColors = array(
-		'aliceblue' => '240,248,255',
-		'antiquewhite' => '250,235,215',
-		'aqua' => '0,255,255',
-		'aquamarine' => '127,255,212',
-		'azure' => '240,255,255',
-		'beige' => '245,245,220',
-		'bisque' => '255,228,196',
-		'black' => '0,0,0',
-		'blanchedalmond' => '255,235,205',
-		'blue' => '0,0,255',
-		'blueviolet' => '138,43,226',
-		'brown' => '165,42,42',
-		'burlywood' => '222,184,135',
-		'cadetblue' => '95,158,160',
-		'chartreuse' => '127,255,0',
-		'chocolate' => '210,105,30',
-		'coral' => '255,127,80',
-		'cornflowerblue' => '100,149,237',
-		'cornsilk' => '255,248,220',
-		'crimson' => '220,20,60',
-		'cyan' => '0,255,255',
-		'darkblue' => '0,0,139',
-		'darkcyan' => '0,139,139',
-		'darkgoldenrod' => '184,134,11',
-		'darkgray' => '169,169,169',
-		'darkgreen' => '0,100,0',
-		'darkgrey' => '169,169,169',
-		'darkkhaki' => '189,183,107',
-		'darkmagenta' => '139,0,139',
-		'darkolivegreen' => '85,107,47',
-		'darkorange' => '255,140,0',
-		'darkorchid' => '153,50,204',
-		'darkred' => '139,0,0',
-		'darksalmon' => '233,150,122',
-		'darkseagreen' => '143,188,143',
-		'darkslateblue' => '72,61,139',
-		'darkslategray' => '47,79,79',
-		'darkslategrey' => '47,79,79',
-		'darkturquoise' => '0,206,209',
-		'darkviolet' => '148,0,211',
-		'deeppink' => '255,20,147',
-		'deepskyblue' => '0,191,255',
-		'dimgray' => '105,105,105',
-		'dimgrey' => '105,105,105',
-		'dodgerblue' => '30,144,255',
-		'firebrick' => '178,34,34',
-		'floralwhite' => '255,250,240',
-		'forestgreen' => '34,139,34',
-		'fuchsia' => '255,0,255',
-		'gainsboro' => '220,220,220',
-		'ghostwhite' => '248,248,255',
-		'gold' => '255,215,0',
-		'goldenrod' => '218,165,32',
-		'gray' => '128,128,128',
-		'green' => '0,128,0',
-		'greenyellow' => '173,255,47',
-		'grey' => '128,128,128',
-		'honeydew' => '240,255,240',
-		'hotpink' => '255,105,180',
-		'indianred' => '205,92,92',
-		'indigo' => '75,0,130',
-		'ivory' => '255,255,240',
-		'khaki' => '240,230,140',
-		'lavender' => '230,230,250',
-		'lavenderblush' => '255,240,245',
-		'lawngreen' => '124,252,0',
-		'lemonchiffon' => '255,250,205',
-		'lightblue' => '173,216,230',
-		'lightcoral' => '240,128,128',
-		'lightcyan' => '224,255,255',
-		'lightgoldenrodyellow' => '250,250,210',
-		'lightgray' => '211,211,211',
-		'lightgreen' => '144,238,144',
-		'lightgrey' => '211,211,211',
-		'lightpink' => '255,182,193',
-		'lightsalmon' => '255,160,122',
-		'lightseagreen' => '32,178,170',
-		'lightskyblue' => '135,206,250',
-		'lightslategray' => '119,136,153',
-		'lightslategrey' => '119,136,153',
-		'lightsteelblue' => '176,196,222',
-		'lightyellow' => '255,255,224',
-		'lime' => '0,255,0',
-		'limegreen' => '50,205,50',
-		'linen' => '250,240,230',
-		'magenta' => '255,0,255',
-		'maroon' => '128,0,0',
-		'mediumaquamarine' => '102,205,170',
-		'mediumblue' => '0,0,205',
-		'mediumorchid' => '186,85,211',
-		'mediumpurple' => '147,112,219',
-		'mediumseagreen' => '60,179,113',
-		'mediumslateblue' => '123,104,238',
-		'mediumspringgreen' => '0,250,154',
-		'mediumturquoise' => '72,209,204',
-		'mediumvioletred' => '199,21,133',
-		'midnightblue' => '25,25,112',
-		'mintcream' => '245,255,250',
-		'mistyrose' => '255,228,225',
-		'moccasin' => '255,228,181',
-		'navajowhite' => '255,222,173',
-		'navy' => '0,0,128',
-		'oldlace' => '253,245,230',
-		'olive' => '128,128,0',
-		'olivedrab' => '107,142,35',
-		'orange' => '255,165,0',
-		'orangered' => '255,69,0',
-		'orchid' => '218,112,214',
-		'palegoldenrod' => '238,232,170',
-		'palegreen' => '152,251,152',
-		'paleturquoise' => '175,238,238',
-		'palevioletred' => '219,112,147',
-		'papayawhip' => '255,239,213',
-		'peachpuff' => '255,218,185',
-		'peru' => '205,133,63',
-		'pink' => '255,192,203',
-		'plum' => '221,160,221',
-		'powderblue' => '176,224,230',
-		'purple' => '128,0,128',
-		'red' => '255,0,0',
-		'rosybrown' => '188,143,143',
-		'royalblue' => '65,105,225',
-		'saddlebrown' => '139,69,19',
-		'salmon' => '250,128,114',
-		'sandybrown' => '244,164,96',
-		'seagreen' => '46,139,87',
-		'seashell' => '255,245,238',
-		'sienna' => '160,82,45',
-		'silver' => '192,192,192',
-		'skyblue' => '135,206,235',
-		'slateblue' => '106,90,205',
-		'slategray' => '112,128,144',
-		'slategrey' => '112,128,144',
-		'snow' => '255,250,250',
-		'springgreen' => '0,255,127',
-		'steelblue' => '70,130,180',
-		'tan' => '210,180,140',
-		'teal' => '0,128,128',
-		'thistle' => '216,191,216',
-		'tomato' => '255,99,71',
-		'transparent' => '0,0,0,0',
-		'turquoise' => '64,224,208',
-		'violet' => '238,130,238',
-		'wheat' => '245,222,179',
-		'white' => '255,255,255',
-		'whitesmoke' => '245,245,245',
-		'yellow' => '255,255,0',
-		'yellowgreen' => '154,205,50'
-	);
-}
-
-// responsible for taking a string of LESS code and converting it into a
-// syntax tree
-class lessc_parser {
-	static protected $nextBlockId = 0; // used to uniquely identify blocks
-
-	static protected $precedence = array(
-		'=<' => 0,
-		'>=' => 0,
-		'=' => 0,
-		'<' => 0,
-		'>' => 0,
-
-		'+' => 1,
-		'-' => 1,
-		'*' => 2,
-		'/' => 2,
-		'%' => 2,
-	);
-
-	static protected $whitePattern;
-	static protected $commentMulti;
-
-	static protected $commentSingle = "//";
-	static protected $commentMultiLeft = "/*";
-	static protected $commentMultiRight = "*/";
-
-	// regex string to match any of the operators
-	static protected $operatorString;
-
-	// these properties will supress division unless it's inside parenthases
-	static protected $supressDivisionProps =
-		array('/border-radius$/i', '/^font$/i');
-
-	protected $blockDirectives = array("font-face", "keyframes", "page", "-moz-document", "viewport", "-moz-viewport", "-o-viewport", "-ms-viewport");
-	protected $lineDirectives = array("charset");
-
-	/**
-	 * if we are in parens we can be more liberal with whitespace around
-	 * operators because it must evaluate to a single value and thus is less
-	 * ambiguous.
-	 *
-	 * Consider:
-	 *     property1: 10 -5; // is two numbers, 10 and -5
-	 *     property2: (10 -5); // should evaluate to 5
-	 */
-	protected $inParens = false;
-
-	// caches preg escaped literals
-	static protected $literalCache = array();
-
-	public function __construct($lessc, $sourceName = null) {
-		$this->eatWhiteDefault = true;
-		// reference to less needed for vPrefix, mPrefix, and parentSelector
-		$this->lessc = $lessc;
-
-		$this->sourceName = $sourceName; // name used for error messages
-
-		$this->writeComments = false;
-
-		if (!self::$operatorString) {
-			self::$operatorString =
-				'('.implode('|', array_map(array('lessc', 'preg_quote'),
-					array_keys(self::$precedence))).')';
-
-			$commentSingle = lessc::preg_quote(self::$commentSingle);
-			$commentMultiLeft = lessc::preg_quote(self::$commentMultiLeft);
-			$commentMultiRight = lessc::preg_quote(self::$commentMultiRight);
-
-			self::$commentMulti = $commentMultiLeft.'.*?'.$commentMultiRight;
-			self::$whitePattern = '/'.$commentSingle.'[^\n]*\s*|('.self::$commentMulti.')\s*|\s+/Ais';
-		}
-	}
-
-	public function parse($buffer) {
-		$this->count = 0;
-		$this->line = 1;
-
-		$this->env = null; // block stack
-		$this->buffer = $this->writeComments ? $buffer : $this->removeComments($buffer);
-		$this->pushSpecialBlock("root");
-		$this->eatWhiteDefault = true;
-		$this->seenComments = array();
-
-		// trim whitespace on head
-		// if (preg_match('/^\s+/', $this->buffer, $m)) {
-		// 	$this->line += substr_count($m[0], "\n");
-		// 	$this->buffer = ltrim($this->buffer);
-		// }
-		$this->whitespace();
-
-		// parse the entire file
-		$lastCount = $this->count;
-		while (false !== $this->parseChunk());
-
-		if ($this->count != strlen($this->buffer))
-			$this->throwError();
-
-		// TODO report where the block was opened
-		if (!property_exists($this->env, 'parent') || !is_null($this->env->parent))
-			throw new exception('parse error: unclosed block');
-
-		return $this->env;
-	}
-
-	/**
-	 * Parse a single chunk off the head of the buffer and append it to the
-	 * current parse environment.
-	 * Returns false when the buffer is empty, or when there is an error.
-	 *
-	 * This function is called repeatedly until the entire document is
-	 * parsed.
-	 *
-	 * This parser is most similar to a recursive descent parser. Single
-	 * functions represent discrete grammatical rules for the language, and
-	 * they are able to capture the text that represents those rules.
-	 *
-	 * Consider the function lessc::keyword(). (all parse functions are
-	 * structured the same)
-	 *
-	 * The function takes a single reference argument. When calling the
-	 * function it will attempt to match a keyword on the head of the buffer.
-	 * If it is successful, it will place the keyword in the referenced
-	 * argument, advance the position in the buffer, and return true. If it
-	 * fails then it won't advance the buffer and it will return false.
-	 *
-	 * All of these parse functions are powered by lessc::match(), which behaves
-	 * the same way, but takes a literal regular expression. Sometimes it is
-	 * more convenient to use match instead of creating a new function.
-	 *
-	 * Because of the format of the functions, to parse an entire string of
-	 * grammatical rules, you can chain them together using &&.
-	 *
-	 * But, if some of the rules in the chain succeed before one fails, then
-	 * the buffer position will be left at an invalid state. In order to
-	 * avoid this, lessc::seek() is used to remember and set buffer positions.
-	 *
-	 * Before parsing a chain, use $s = $this->seek() to remember the current
-	 * position into $s. Then if a chain fails, use $this->seek($s) to
-	 * go back where we started.
-	 */
-	protected function parseChunk() {
-		if (empty($this->buffer)) return false;
-		$s = $this->seek();
-
-		// setting a property
-		if ($this->keyword($key) && $this->assign() &&
-			$this->propertyValue($value, $key) && $this->end())
-		{
-			$this->append(array('assign', $key, $value), $s);
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-
-		// look for special css blocks
-		if ($this->literal('@', false)) {
-			$this->count--;
-
-			// media
-			if ($this->literal('@media')) {
-				if (($this->mediaQueryList($mediaQueries) || true)
-					&& $this->literal('{'))
-				{
-					$media = $this->pushSpecialBlock("media");
-					$media->queries = is_null($mediaQueries) ? array() : $mediaQueries;
-					return true;
-				} else {
-					$this->seek($s);
-					return false;
-				}
-			}
-
-			if ($this->literal("@", false) && $this->keyword($dirName)) {
-				if ($this->isDirective($dirName, $this->blockDirectives)) {
-					if (($this->openString("{", $dirValue, null, array(";")) || true) &&
-						$this->literal("{"))
-					{
-						$dir = $this->pushSpecialBlock("directive");
-						$dir->name = $dirName;
-						if (isset($dirValue)) $dir->value = $dirValue;
-						return true;
-					}
-				} elseif ($this->isDirective($dirName, $this->lineDirectives)) {
-					if ($this->propertyValue($dirValue) && $this->end()) {
-						$this->append(array("directive", $dirName, $dirValue));
-						return true;
-					}
-				}
-			}
-
-			$this->seek($s);
-		}
-
-		// setting a variable
-		if ($this->variable($var) && $this->assign() &&
-			$this->propertyValue($value) && $this->end())
-		{
-			$this->append(array('assign', $var, $value), $s);
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-		if ($this->import($importValue)) {
-			$this->append($importValue, $s);
-			return true;
-		}
-
-		// opening parametric mixin
-		if ($this->tag($tag, true) && $this->argumentDef($args, $isVararg) &&
-			($this->guards($guards) || true) &&
-			$this->literal('{'))
-		{
-			$block = $this->pushBlock($this->fixTags(array($tag)));
-			$block->args = $args;
-			$block->isVararg = $isVararg;
-			if (!empty($guards)) $block->guards = $guards;
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-		// opening a simple block
-		if ($this->tags($tags) && $this->literal('{')) {
-			$tags = $this->fixTags($tags);
-			$this->pushBlock($tags);
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-		// closing a block
-		if ($this->literal('}', false)) {
-			try {
-				$block = $this->pop();
-			} catch (exception $e) {
-				$this->seek($s);
-				$this->throwError($e->getMessage());
-			}
-
-			$hidden = false;
-			if (is_null($block->type)) {
-				$hidden = true;
-				if (!isset($block->args)) {
-					foreach ($block->tags as $tag) {
-						if (!is_string($tag) || $tag{0} != $this->lessc->mPrefix) {
-							$hidden = false;
-							break;
-						}
-					}
-				}
-
-				foreach ($block->tags as $tag) {
-					if (is_string($tag)) {
-						$this->env->children[$tag][] = $block;
-					}
-				}
-			}
-
-			if (!$hidden) {
-				$this->append(array('block', $block), $s);
-			}
-
-			// this is done here so comments aren't bundled into he block that
-			// was just closed
-			$this->whitespace();
-			return true;
-		}
-
-		// mixin
-		if ($this->mixinTags($tags) &&
-			($this->argumentDef($argv, $isVararg) || true) &&
-			($this->keyword($suffix) || true) && $this->end())
-		{
-			$tags = $this->fixTags($tags);
-			$this->append(array('mixin', $tags, $argv, $suffix), $s);
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-		// spare ;
-		if ($this->literal(';')) return true;
-
-		return false; // got nothing, throw error
-	}
-
-	protected function isDirective($dirname, $directives) {
-		// TODO: cache pattern in parser
-		$pattern = implode("|",
-			array_map(array("lessc", "preg_quote"), $directives));
-		$pattern = '/^(-[a-z-]+-)?(' . $pattern . ')$/i';
-
-		return preg_match($pattern, $dirname);
-	}
-
-	protected function fixTags($tags) {
-		// move @ tags out of variable namespace
-		foreach ($tags as &$tag) {
-			if ($tag{0} == $this->lessc->vPrefix)
-				$tag[0] = $this->lessc->mPrefix;
-		}
-		return $tags;
-	}
-
-	// a list of expressions
-	protected function expressionList(&$exps) {
-		$values = array();
-
-		while ($this->expression($exp)) {
-			$values[] = $exp;
-		}
-
-		if (count($values) == 0) return false;
-
-		$exps = lessc::compressList($values, ' ');
-		return true;
-	}
-
-	/**
-	 * Attempt to consume an expression.
-	 * @link http://en.wikipedia.org/wiki/Operator-precedence_parser#Pseudo-code
-	 */
-	protected function expression(&$out) {
-		if ($this->value($lhs)) {
-			$out = $this->expHelper($lhs, 0);
-
-			// look for / shorthand
-			if (!empty($this->env->supressedDivision)) {
-				unset($this->env->supressedDivision);
-				$s = $this->seek();
-				if ($this->literal("/") && $this->value($rhs)) {
-					$out = array("list", "",
-						array($out, array("keyword", "/"), $rhs));
-				} else {
-					$this->seek($s);
-				}
-			}
-
-			return true;
-		}
-		return false;
-	}
-
-	/**
-	 * recursively parse infix equation with $lhs at precedence $minP
-	 */
-	protected function expHelper($lhs, $minP) {
-		$this->inExp = true;
-		$ss = $this->seek();
-
-		while (true) {
-			$whiteBefore = isset($this->buffer[$this->count - 1]) &&
-				ctype_space($this->buffer[$this->count - 1]);
-
-			// If there is whitespace before the operator, then we require
-			// whitespace after the operator for it to be an expression
-			$needWhite = $whiteBefore && !$this->inParens;
-
-			if ($this->match(self::$operatorString.($needWhite ? '\s' : ''), $m) && self::$precedence[$m[1]] >= $minP) {
-				if (!$this->inParens && isset($this->env->currentProperty) && $m[1] == "/" && empty($this->env->supressedDivision)) {
-					foreach (self::$supressDivisionProps as $pattern) {
-						if (preg_match($pattern, $this->env->currentProperty)) {
-							$this->env->supressedDivision = true;
-							break 2;
-						}
-					}
-				}
-
-
-				$whiteAfter = isset($this->buffer[$this->count - 1]) &&
-					ctype_space($this->buffer[$this->count - 1]);
-
-				if (!$this->value($rhs)) break;
-
-				// peek for next operator to see what to do with rhs
-				if ($this->peek(self::$operatorString, $next) && self::$precedence[$next[1]] > self::$precedence[$m[1]]) {
-					$rhs = $this->expHelper($rhs, self::$precedence[$next[1]]);
-				}
-
-				$lhs = array('expression', $m[1], $lhs, $rhs, $whiteBefore, $whiteAfter);
-				$ss = $this->seek();
-
-				continue;
-			}
-
-			break;
-		}
-
-		$this->seek($ss);
-
-		return $lhs;
-	}
-
-	// consume a list of values for a property
-	public function propertyValue(&$value, $keyName = null) {
-		$values = array();
-
-		if ($keyName !== null) $this->env->currentProperty = $keyName;
-
-		$s = null;
-		while ($this->expressionList($v)) {
-			$values[] = $v;
-			$s = $this->seek();
-			if (!$this->literal(',')) break;
-		}
-
-		if ($s) $this->seek($s);
-
-		if ($keyName !== null) unset($this->env->currentProperty);
-
-		if (count($values) == 0) return false;
-
-		$value = lessc::compressList($values, ', ');
-		return true;
-	}
-
-	protected function parenValue(&$out) {
-		$s = $this->seek();
-
-		// speed shortcut
-		if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "(") {
-			return false;
-		}
-
-		$inParens = $this->inParens;
-		if ($this->literal("(") &&
-			($this->inParens = true) && $this->expression($exp) &&
-			$this->literal(")"))
-		{
-			$out = $exp;
-			$this->inParens = $inParens;
-			return true;
-		} else {
-			$this->inParens = $inParens;
-			$this->seek($s);
-		}
-
-		return false;
-	}
-
-	// a single value
-	protected function value(&$value) {
-		$s = $this->seek();
-
-		// speed shortcut
-		if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "-") {
-			// negation
-			if ($this->literal("-", false) &&
-				(($this->variable($inner) && $inner = array("variable", $inner)) ||
-				$this->unit($inner) ||
-				$this->parenValue($inner)))
-			{
-				$value = array("unary", "-", $inner);
-				return true;
-			} else {
-				$this->seek($s);
-			}
-		}
-
-		if ($this->parenValue($value)) return true;
-		if ($this->unit($value)) return true;
-		if ($this->color($value)) return true;
-		if ($this->func($value)) return true;
-		if ($this->string($value)) return true;
-
-		if ($this->keyword($word)) {
-			$value = array('keyword', $word);
-			return true;
-		}
-
-		// try a variable
-		if ($this->variable($var)) {
-			$value = array('variable', $var);
-			return true;
-		}
-
-		// unquote string (should this work on any type?
-		if ($this->literal("~") && $this->string($str)) {
-			$value = array("escape", $str);
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-		// css hack: \0
-		if ($this->literal('\\') && $this->match('([0-9]+)', $m)) {
-			$value = array('keyword', '\\'.$m[1]);
-			return true;
-		} else {
-			$this->seek($s);
-		}
-
-		return false;
-	}
-
-	// an import statement
-	protected function import(&$out) {
-		$s = $this->seek();
-		if (!$this->literal('@import')) return false;
-
-		// @import "something.css" media;
-		// @import url("something.css") media;
-		// @import url(something.css) media;
-
-		if ($this->propertyValue($value)) {
-			$out = array("import", $value);
-			return true;
-		}
-	}
-
-	protected function mediaQueryList(&$out) {
-		if ($this->genericList($list, "mediaQuery", ",", false)) {
-			$out = $list[2];
-			return true;
-		}
-		return false;
-	}
-
-	protected function mediaQuery(&$out) {
-		$s = $this->seek();
-
-		$expressions = null;
-		$parts = array();
-
-		if (($this->literal("only") && ($only = true) || $this->literal("not") && ($not = true) || true) && $this->keyword($mediaType)) {
-			$prop = array("mediaType");
-			if (isset($only)) $prop[] = "only";
-			if (isset($not)) $prop[] = "not";
-			$prop[] = $mediaType;
-			$parts[] = $prop;
-		} else {
-			$this->seek($s);
-		}
-
-
-		if (!empty($mediaType) && !$this->literal("and")) {
-			// ~
-		} else {
-			$this->genericList($expressions, "mediaExpression", "and", false);
-			if (is_array($expressions)) $parts = array_merge($parts, $expressions[2]);
-		}
-
-		if (count($parts) == 0) {
-			$this->seek($s);
-			return false;
-		}
-
-		$out = $parts;
-		return true;
-	}
-
-	protected function mediaExpression(&$out) {
-		$s = $this->seek();
-		$value = null;
-		if ($this->literal("(") &&
-			$this->keyword($feature) &&
-			($this->literal(":") && $this->expression($value) || true) &&
-			$this->literal(")"))
-		{
-			$out = array("mediaExp", $feature);
-			if ($value) $out[] = $value;
-			return true;
-		} elseif ($this->variable($variable)) {
-			$out = array('variable', $variable);
-			return true;
-		}
-
-		$this->seek($s);
-		return false;
-	}
-
-	// an unbounded string stopped by $end
-	protected function openString($end, &$out, $nestingOpen=null, $rejectStrs = null) {
-		$oldWhite = $this->eatWhiteDefault;
-		$this->eatWhiteDefault = false;
-
-		$stop = array("'", '"', "@{", $end);
-		$stop = array_map(array("lessc", "preg_quote"), $stop);
-		// $stop[] = self::$commentMulti;
-
-		if (!is_null($rejectStrs)) {
-			$stop = array_merge($stop, $rejectStrs);
-		}
-
-		$patt = '(.*?)('.implode("|", $stop).')';
-
-		$nestingLevel = 0;
-
-		$content = array();
-		while ($this->match($patt, $m, false)) {
-			if (!empty($m[1])) {
-				$content[] = $m[1];
-				if ($nestingOpen) {
-					$nestingLevel += substr_count($m[1], $nestingOpen);
-				}
-			}
-
-			$tok = $m[2];
-
-			$this->count-= strlen($tok);
-			if ($tok == $end) {
-				if ($nestingLevel == 0) {
-					break;
-				} else {
-					$nestingLevel--;
-				}
-			}
-
-			if (($tok == "'" || $tok == '"') && $this->string($str)) {
-				$content[] = $str;
-				continue;
-			}
-
-			if ($tok == "@{" && $this->interpolation($inter)) {
-				$content[] = $inter;
-				continue;
-			}
-
-			if (!empty($rejectStrs) && in_array($tok, $rejectStrs)) {
-				break;
-			}
-
-			$content[] = $tok;
-			$this->count+= strlen($tok);
-		}
-
-		$this->eatWhiteDefault = $oldWhite;
-
-		if (count($content) == 0) return false;
-
-		// trim the end
-		if (is_string(end($content))) {
-			$content[count($content) - 1] = rtrim(end($content));
-		}
-
-		$out = array("string", "", $content);
-		return true;
-	}
-
-	protected function string(&$out) {
-		$s = $this->seek();
-		if ($this->literal('"', false)) {
-			$delim = '"';
-		} elseif ($this->literal("'", false)) {
-			$delim = "'";
-		} else {
-			return false;
-		}
-
-		$content = array();
-
-		// look for either ending delim , escape, or string interpolation
-		$patt = '([^\n]*?)(@\{|\\\\|' .
-			lessc::preg_quote($delim).')';
-
-		$oldWhite = $this->eatWhiteDefault;
-		$this->eatWhiteDefault = false;
-
-		while ($this->match($patt, $m, false)) {
-			$content[] = $m[1];
-			if ($m[2] == "@{") {
-				$this->count -= strlen($m[2]);
-				if ($this->interpolation($inter, false)) {
-					$content[] = $inter;
-				} else {
-					$this->count += strlen($m[2]);
-					$content[] = "@{"; // ignore it
-				}
-			} elseif ($m[2] == '\\') {
-				$content[] = $m[2];
-				if ($this->literal($delim, false)) {
-					$content[] = $delim;
-				}
-			} else {
-				$this->count -= strlen($delim);
-				break; // delim
-			}
-		}
-
-		$this->eatWhiteDefault = $oldWhite;
-
-		if ($this->literal($delim)) {
-			$out = array("string", $delim, $content);
-			return true;
-		}
-
-		$this->seek($s);
-		return false;
-	}
-
-	protected function interpolation(&$out) {
-		$oldWhite = $this->eatWhiteDefault;
-		$this->eatWhiteDefault = true;
-
-		$s = $this->seek();
-		if ($this->literal("@{") &&
-			$this->openString("}", $interp, null, array("'", '"', ";")) &&
-			$this->literal("}", false))
-		{
-			$out = array("interpolate", $interp);
-			$this->eatWhiteDefault = $oldWhite;
-			if ($this->eatWhiteDefault) $this->whitespace();
-			return true;
-		}
-
-		$this->eatWhiteDefault = $oldWhite;
-		$this->seek($s);
-		return false;
-	}
-
-	protected function unit(&$unit) {
-		// speed shortcut
-		if (isset($this->buffer[$this->count])) {
-			$char = $this->buffer[$this->count];
-			if (!ctype_digit($char) && $char != ".") return false;
-		}
-
-		if ($this->match('([0-9]+(?:\.[0-9]*)?|\.[0-9]+)([%a-zA-Z]+)?', $m)) {
-			$unit = array("number", $m[1], empty($m[2]) ? "" : $m[2]);
-			return true;
-		}
-		return false;
-	}
-
-	// a # color
-	protected function color(&$out) {
-		if ($this->match('(#(?:[0-9a-f]{8}|[0-9a-f]{6}|[0-9a-f]{3}))', $m)) {
-			if (strlen($m[1]) > 7) {
-				$out = array("string", "", array($m[1]));
-			} else {
-				$out = array("raw_color", $m[1]);
-			}
-			return true;
-		}
-
-		return false;
-	}
-
-	// consume an argument definition list surrounded by ()
-	// each argument is a variable name with optional value
-	// or at the end a ... or a variable named followed by ...
-	// arguments are separated by , unless a ; is in the list, then ; is the
-	// delimiter.
-	protected function argumentDef(&$args, &$isVararg) {
-		$s = $this->seek();
-		if (!$this->literal('(')) return false;
-
-		$values = array();
-		$delim = ",";
-		$method = "expressionList";
-
-		$isVararg = false;
-		while (true) {
-			if ($this->literal("...")) {
-				$isVararg = true;
-				break;
-			}
-
-			if ($this->$method($value)) {
-				if ($value[0] == "variable") {
-					$arg = array("arg", $value[1]);
-					$ss = $this->seek();
-
-					if ($this->assign() && $this->$method($rhs)) {
-						$arg[] = $rhs;
-					} else {
-						$this->seek($ss);
-						if ($this->literal("...")) {
-							$arg[0] = "rest";
-							$isVararg = true;
-						}
-					}
-
-					$values[] = $arg;
-					if ($isVararg) break;
-					continue;
-				} else {
-					$values[] = array("lit", $value);
-				}
-			}
-
-
-			if (!$this->literal($delim)) {
-				if ($delim == "," && $this->literal(";")) {
-					// found new delim, convert existing args
-					$delim = ";";
-					$method = "propertyValue";
-
-					// transform arg list
-					if (isset($values[1])) { // 2 items
-						$newList = array();
-						foreach ($values as $i => $arg) {
-							switch($arg[0]) {
-							case "arg":
-								if ($i) {
-									$this->throwError("Cannot mix ; and , as delimiter types");
-								}
-								$newList[] = $arg[2];
-								break;
-							case "lit":
-								$newList[] = $arg[1];
-								break;
-							case "rest":
-								$this->throwError("Unexpected rest before semicolon");
-							}
-						}
-
-						$newList = array("list", ", ", $newList);
-
-						switch ($values[0][0]) {
-						case "arg":
-							$newArg = array("arg", $values[0][1], $newList);
-							break;
-						case "lit":
-							$newArg = array("lit", $newList);
-							break;
-						}
-
-					} elseif ($values) { // 1 item
-						$newArg = $values[0];
-					}
-
-					if ($newArg) {
-						$values = array($newArg);
-					}
-				} else {
-					break;
-				}
-			}
-		}
-
-		if (!$this->literal(')')) {
-			$this->seek($s);
-			return false;
-		}
-
-		$args = $values;
-
-		return true;
-	}
-
-	// consume a list of tags
-	// this accepts a hanging delimiter
-	protected function tags(&$tags, $simple = false, $delim = ',') {
-		$tags = array();
-		while ($this->tag($tt, $simple)) {
-			$tags[] = $tt;
-			if (!$this->literal($delim)) break;
-		}
-		if (count($tags) == 0) return false;
-
-		return true;
-	}
-
-	// list of tags of specifying mixin path
-	// optionally separated by > (lazy, accepts extra >)
-	protected function mixinTags(&$tags) {
-		$s = $this->seek();
-		$tags = array();
-		while ($this->tag($tt, true)) {
-			$tags[] = $tt;
-			$this->literal(">");
-		}
-
-		if (count($tags) == 0) return false;
-
-		return true;
-	}
-
-	// a bracketed value (contained within in a tag definition)
-	protected function tagBracket(&$parts, &$hasExpression) {
-		// speed shortcut
-		if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "[") {
-			return false;
-		}
-
-		$s = $this->seek();
-
-		$hasInterpolation = false;
-
-		if ($this->literal("[", false)) {
-			$attrParts = array("[");
-			// keyword, string, operator
-			while (true) {
-				if ($this->literal("]", false)) {
-					$this->count--;
-					break; // get out early
-				}
-
-				if ($this->match('\s+', $m)) {
-					$attrParts[] = " ";
-					continue;
-				}
-				if ($this->string($str)) {
-					// escape parent selector, (yuck)
-					foreach ($str[2] as &$chunk) {
-						$chunk = str_replace($this->lessc->parentSelector, "$&$", $chunk);
-					}
-
-					$attrParts[] = $str;
-					$hasInterpolation = true;
-					continue;
-				}
-
-				if ($this->keyword($word)) {
-					$attrParts[] = $word;
-					continue;
-				}
-
-				if ($this->interpolation($inter, false)) {
-					$attrParts[] = $inter;
-					$hasInterpolation = true;
-					continue;
-				}
-
-				// operator, handles attr namespace too
-				if ($this->match('[|-~\$\*\^=]+', $m)) {
-					$attrParts[] = $m[0];
-					continue;
-				}
-
-				break;
-			}
-
-			if ($this->literal("]", false)) {
-				$attrParts[] = "]";
-				foreach ($attrParts as $part) {
-					$parts[] = $part;
-				}
-				$hasExpression = $hasExpression || $hasInterpolation;
-				return true;
-			}
-			$this->seek($s);
-		}
-
-		$this->seek($s);
-		return false;
-	}
-
-	// a space separated list of selectors
-	protected function tag(&$tag, $simple = false) {
-		if ($simple)
-			$chars = '^@,:;{}\][>\(\) "\'';
-		else
-			$chars = '^@,;{}["\'';
-
-		$s = $this->seek();
-
-		$hasExpression = false;
-		$parts = array();
-		while ($this->tagBracket($parts, $hasExpression));
-
-		$oldWhite = $this->eatWhiteDefault;
-		$this->eatWhiteDefault = false;
-
-		while (true) {
-			if ($this->match('(['.$chars.'0-9]['.$chars.']*)', $m)) {
-				$parts[] = $m[1];
-				if ($simple) break;
-
-				while ($this->tagBracket($parts, $hasExpression));
-				continue;
-			}
-
-			if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "@") {
-				if ($this->interpolation($interp)) {
-					$hasExpression = true;
-					$interp[2] = true; // don't unescape
-					$parts[] = $interp;
-					continue;
-				}
-
-				if ($this->literal("@")) {
-					$parts[] = "@";
-					continue;
-				}
-			}
-
-			if ($this->unit($unit)) { // for keyframes
-				$parts[] = $unit[1];
-				$parts[] = $unit[2];
-				continue;
-			}
-
-			break;
-		}
-
-		$this->eatWhiteDefault = $oldWhite;
-		if (!$parts) {
-			$this->seek($s);
-			return false;
-		}
-
-		if ($hasExpression) {
-			$tag = array("exp", array("string", "", $parts));
-		} else {
-			$tag = trim(implode($parts));
-		}
-
-		$this->whitespace();
-		return true;
-	}
-
-	// a css function
-	protected function func(&$func) {
-		$s = $this->seek();
-
-		if ($this->match('(%|[\w\-_][\w\-_:\.]+|[\w_])', $m) && $this->literal('(')) {
-			$fname = $m[1];
-
-			$sPreArgs = $this->seek();
-
-			$args = array();
-			while (true) {
-				$ss = $this->seek();
-				// this ugly nonsense is for ie filter properties
-				if ($this->keyword($name) && $this->literal('=') && $this->expressionList($value)) {
-					$args[] = array("string", "", array($name, "=", $value));
-				} else {
-					$this->seek($ss);
-					if ($this->expressionList($value)) {
-						$args[] = $value;
-					}
-				}
-
-				if (!$this->literal(',')) break;
-			}
-			$args = array('list', ',', $args);
-
-			if ($this->literal(')')) {
-				$func = array('function', $fname, $args);
-				return true;
-			} elseif ($fname == 'url') {
-				// couldn't parse and in url? treat as string
-				$this->seek($sPreArgs);
-				if ($this->openString(")", $string) && $this->literal(")")) {
-					$func = array('function', $fname, $string);
-					return true;
-				}
-			}
-		}
-
-		$this->seek($s);
-		return false;
-	}
-
-	// consume a less variable
-	protected function variable(&$name) {
-		$s = $this->seek();
-		if ($this->literal($this->lessc->vPrefix, false) &&
-			($this->variable($sub) || $this->keyword($name)))
-		{
-			if (!empty($sub)) {
-				$name = array('variable', $sub);
-			} else {
-				$name = $this->lessc->vPrefix.$name;
-			}
-			return true;
-		}
-
-		$name = null;
-		$this->seek($s);
-		return false;
-	}
-
-	/**
-	 * Consume an assignment operator
-	 * Can optionally take a name that will be set to the current property name
-	 */
-	protected function assign($name = null) {
-		if ($name) $this->currentProperty = $name;
-		return $this->literal(':') || $this->literal('=');
-	}
-
-	// consume a keyword
-	protected function keyword(&$word) {
-		if ($this->match('([\w_\-\*!"][\w\-_"]*)', $m)) {
-			$word = $m[1];
-			return true;
-		}
-		return false;
-	}
-
-	// consume an end of statement delimiter
-	protected function end() {
-		if ($this->literal(';')) {
-			return true;
-		} elseif ($this->count == strlen($this->buffer) || $this->buffer[$this->count] == '}') {
-			// if there is end of file or a closing block next then we don't need a ;
-			return true;
-		}
-		return false;
-	}
-
-	protected function guards(&$guards) {
-		$s = $this->seek();
-
-		if (!$this->literal("when")) {
-			$this->seek($s);
-			return false;
-		}
-
-		$guards = array();
-
-		while ($this->guardGroup($g)) {
-			$guards[] = $g;
-			if (!$this->literal(",")) break;
-		}
-
-		if (count($guards) == 0) {
-			$guards = null;
-			$this->seek($s);
-			return false;
-		}
-
-		return true;
-	}
-
-	// a bunch of guards that are and'd together
-	// TODO rename to guardGroup
-	protected function guardGroup(&$guardGroup) {
-		$s = $this->seek();
-		$guardGroup = array();
-		while ($this->guard($guard)) {
-			$guardGroup[] = $guard;
-			if (!$this->literal("and")) break;
-		}
-
-		if (count($guardGroup) == 0) {
-			$guardGroup = null;
-			$this->seek($s);
-			return false;
-		}
-
-		return true;
-	}
-
-	protected function guard(&$guard) {
-		$s = $this->seek();
-		$negate = $this->literal("not");
-
-		if ($this->literal("(") && $this->expression($exp) && $this->literal(")")) {
-			$guard = $exp;
-			if ($negate) $guard = array("negate", $guard);
-			return true;
-		}
-
-		$this->seek($s);
-		return false;
-	}
-
-	/* raw parsing functions */
-
-	protected function literal($what, $eatWhitespace = null) {
-		if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
-
-		// shortcut on single letter
-		if (!isset($what[1]) && isset($this->buffer[$this->count])) {
-			if ($this->buffer[$this->count] == $what) {
-				if (!$eatWhitespace) {
-					$this->count++;
-					return true;
-				}
-				// goes below...
-			} else {
-				return false;
-			}
-		}
-
-		if (!isset(self::$literalCache[$what])) {
-			self::$literalCache[$what] = lessc::preg_quote($what);
-		}
-
-		return $this->match(self::$literalCache[$what], $m, $eatWhitespace);
-	}
-
-	protected function genericList(&$out, $parseItem, $delim="", $flatten=true) {
-		$s = $this->seek();
-		$items = array();
-		while ($this->$parseItem($value)) {
-			$items[] = $value;
-			if ($delim) {
-				if (!$this->literal($delim)) break;
-			}
-		}
-
-		if (count($items) == 0) {
-			$this->seek($s);
-			return false;
-		}
-
-		if ($flatten && count($items) == 1) {
-			$out = $items[0];
-		} else {
-			$out = array("list", $delim, $items);
-		}
-
-		return true;
-	}
-
-
-	// advance counter to next occurrence of $what
-	// $until - don't include $what in advance
-	// $allowNewline, if string, will be used as valid char set
-	protected function to($what, &$out, $until = false, $allowNewline = false) {
-		if (is_string($allowNewline)) {
-			$validChars = $allowNewline;
-		} else {
-			$validChars = $allowNewline ? "." : "[^\n]";
-		}
-		if (!$this->match('('.$validChars.'*?)'.lessc::preg_quote($what), $m, !$until)) return false;
-		if ($until) $this->count -= strlen($what); // give back $what
-		$out = $m[1];
-		return true;
-	}
-
-	// try to match something on head of buffer
-	protected function match($regex, &$out, $eatWhitespace = null) {
-		if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
-
-		$r = '/'.$regex.($eatWhitespace && !$this->writeComments ? '\s*' : '').'/Ais';
-		if (preg_match($r, $this->buffer, $out, null, $this->count)) {
-			$this->count += strlen($out[0]);
-			if ($eatWhitespace && $this->writeComments) $this->whitespace();
-			return true;
-		}
-		return false;
-	}
-
-	// match some whitespace
-	protected function whitespace() {
-		if ($this->writeComments) {
-			$gotWhite = false;
-			while (preg_match(self::$whitePattern, $this->buffer, $m, null, $this->count)) {
-				if (isset($m[1]) && empty($this->commentsSeen[$this->count])) {
-					$this->append(array("comment", $m[1]));
-					$this->commentsSeen[$this->count] = true;
-				}
-				$this->count += strlen($m[0]);
-				$gotWhite = true;
-			}
-			return $gotWhite;
-		} else {
-			$this->match("", $m);
-			return strlen($m[0]) > 0;
-		}
-	}
-
-	// match something without consuming it
-	protected function peek($regex, &$out = null, $from=null) {
-		if (is_null($from)) $from = $this->count;
-		$r = '/'.$regex.'/Ais';
-		$result = preg_match($r, $this->buffer, $out, null, $from);
-
-		return $result;
-	}
-
-	// seek to a spot in the buffer or return where we are on no argument
-	protected function seek($where = null) {
-		if ($where === null) return $this->count;
-		else $this->count = $where;
-		return true;
-	}
-
-	/* misc functions */
-
-	public function throwError($msg = "parse error", $count = null) {
-		$count = is_null($count) ? $this->count : $count;
-
-		$line = $this->line +
-			substr_count(substr($this->buffer, 0, $count), "\n");
-
-		if (!empty($this->sourceName)) {
-			$loc = "$this->sourceName on line $line";
-		} else {
-			$loc = "line: $line";
-		}
-
-		// TODO this depends on $this->count
-		if ($this->peek("(.*?)(\n|$)", $m, $count)) {
-			throw new exception("$msg: failed at `$m[1]` $loc");
-		} else {
-			throw new exception("$msg: $loc");
-		}
-	}
-
-	protected function pushBlock($selectors=null, $type=null) {
-		$b = new stdclass;
-		$b->parent = $this->env;
-
-		$b->type = $type;
-		$b->id = self::$nextBlockId++;
-
-		$b->isVararg = false; // TODO: kill me from here
-		$b->tags = $selectors;
-
-		$b->props = array();
-		$b->children = array();
-
-		$this->env = $b;
-		return $b;
-	}
-
-	// push a block that doesn't multiply tags
-	protected function pushSpecialBlock($type) {
-		return $this->pushBlock(null, $type);
-	}
-
-	// append a property to the current block
-	protected function append($prop, $pos = null) {
-		if ($pos !== null) $prop[-1] = $pos;
-		$this->env->props[] = $prop;
-	}
-
-	// pop something off the stack
-	protected function pop() {
-		$old = $this->env;
-		$this->env = $this->env->parent;
-		return $old;
-	}
-
-	// remove comments from $text
-	// todo: make it work for all functions, not just url
-	protected function removeComments($text) {
-		$look = array(
-			'url(', '//', '/*', '"', "'"
-		);
-
-		$out = '';
-		$min = null;
-		while (true) {
-			// find the next item
-			foreach ($look as $token) {
-				$pos = strpos($text, $token);
-				if ($pos !== false) {
-					if (!isset($min) || $pos < $min[1]) $min = array($token, $pos);
-				}
-			}
-
-			if (is_null($min)) break;
-
-			$count = $min[1];
-			$skip = 0;
-			$newlines = 0;
-			switch ($min[0]) {
-			case 'url(':
-				if (preg_match('/url\(.*?\)/', $text, $m, 0, $count))
-					$count += strlen($m[0]) - strlen($min[0]);
-				break;
-			case '"':
-			case "'":
-				if (preg_match('/'.$min[0].'.*?(?indentLevel = 0;
-	}
-
-	public function indentStr($n = 0) {
-		return str_repeat($this->indentChar, max($this->indentLevel + $n, 0));
-	}
-
-	public function property($name, $value) {
-		return $name . $this->assignSeparator . $value . ";";
-	}
-
-	protected function isEmpty($block) {
-		if (empty($block->lines)) {
-			foreach ($block->children as $child) {
-				if (!$this->isEmpty($child)) return false;
-			}
-
-			return true;
-		}
-		return false;
-	}
-
-	public function block($block) {
-		if ($this->isEmpty($block)) return;
-
-		$inner = $pre = $this->indentStr();
-
-		$isSingle = !$this->disableSingle &&
-			is_null($block->type) && count($block->lines) == 1;
-
-		if (!empty($block->selectors)) {
-			$this->indentLevel++;
-
-			if ($this->breakSelectors) {
-				$selectorSeparator = $this->selectorSeparator . $this->break . $pre;
-			} else {
-				$selectorSeparator = $this->selectorSeparator;
-			}
-
-			echo $pre .
-				implode($selectorSeparator, $block->selectors);
-			if ($isSingle) {
-				echo $this->openSingle;
-				$inner = "";
-			} else {
-				echo $this->open . $this->break;
-				$inner = $this->indentStr();
-			}
-
-		}
-
-		if (!empty($block->lines)) {
-			$glue = $this->break.$inner;
-			echo $inner . implode($glue, $block->lines);
-			if (!$isSingle && !empty($block->children)) {
-				echo $this->break;
-			}
-		}
-
-		foreach ($block->children as $child) {
-			$this->block($child);
-		}
-
-		if (!empty($block->selectors)) {
-			if (!$isSingle && empty($block->children)) echo $this->break;
-
-			if ($isSingle) {
-				echo $this->closeSingle . $this->break;
-			} else {
-				echo $pre . $this->close . $this->break;
-			}
-
-			$this->indentLevel--;
-		}
-	}
-}
-
-class lessc_formatter_compressed extends lessc_formatter_classic {
-	public $disableSingle = true;
-	public $open = "{";
-	public $selectorSeparator = ",";
-	public $assignSeparator = ":";
-	public $break = "";
-	public $compressColors = true;
-
-	public function indentStr($n = 0) {
-		return "";
-	}
-}
-
-class lessc_formatter_lessjs extends lessc_formatter_classic {
-	public $disableSingle = true;
-	public $breakSelectors = true;
-	public $assignSeparator = ": ";
-	public $selectorSeparator = ",";
-}
-
-
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/classmap.php b/wcfsetup/install/files/lib/system/style/scssphp/classmap.php
new file mode 100644
index 0000000000..2d8a52b8e5
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/classmap.php
@@ -0,0 +1,63 @@
+
+ */
+class Range
+{
+    public $first;
+    public $last;
+
+    /**
+     * Initialize range
+     *
+     * @param integer|float $first
+     * @param integer|float $last
+     */
+    public function __construct($first, $last)
+    {
+        $this->first = $first;
+        $this->last = $last;
+    }
+
+    /**
+     * Test for inclusion in range
+     *
+     * @param integer|float $value
+     *
+     * @return boolean
+     */
+    public function includes($value)
+    {
+        return $value >= $this->first && $value <= $this->last;
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Colors.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Colors.php
new file mode 100644
index 0000000000..dd32be2146
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Colors.php
@@ -0,0 +1,176 @@
+
+ */
+class Colors
+{
+    /**
+     * CSS Colors
+     *
+     * @see http://www.w3.org/TR/css3-color
+     */
+    public static $cssColors = array(
+        'aliceblue' => '240,248,255',
+        'antiquewhite' => '250,235,215',
+        'aqua' => '0,255,255',
+        'aquamarine' => '127,255,212',
+        'azure' => '240,255,255',
+        'beige' => '245,245,220',
+        'bisque' => '255,228,196',
+        'black' => '0,0,0',
+        'blanchedalmond' => '255,235,205',
+        'blue' => '0,0,255',
+        'blueviolet' => '138,43,226',
+        'brown' => '165,42,42',
+        'burlywood' => '222,184,135',
+        'cadetblue' => '95,158,160',
+        'chartreuse' => '127,255,0',
+        'chocolate' => '210,105,30',
+        'coral' => '255,127,80',
+        'cornflowerblue' => '100,149,237',
+        'cornsilk' => '255,248,220',
+        'crimson' => '220,20,60',
+        'cyan' => '0,255,255',
+        'darkblue' => '0,0,139',
+        'darkcyan' => '0,139,139',
+        'darkgoldenrod' => '184,134,11',
+        'darkgray' => '169,169,169',
+        'darkgreen' => '0,100,0',
+        'darkgrey' => '169,169,169',
+        'darkkhaki' => '189,183,107',
+        'darkmagenta' => '139,0,139',
+        'darkolivegreen' => '85,107,47',
+        'darkorange' => '255,140,0',
+        'darkorchid' => '153,50,204',
+        'darkred' => '139,0,0',
+        'darksalmon' => '233,150,122',
+        'darkseagreen' => '143,188,143',
+        'darkslateblue' => '72,61,139',
+        'darkslategray' => '47,79,79',
+        'darkslategrey' => '47,79,79',
+        'darkturquoise' => '0,206,209',
+        'darkviolet' => '148,0,211',
+        'deeppink' => '255,20,147',
+        'deepskyblue' => '0,191,255',
+        'dimgray' => '105,105,105',
+        'dimgrey' => '105,105,105',
+        'dodgerblue' => '30,144,255',
+        'firebrick' => '178,34,34',
+        'floralwhite' => '255,250,240',
+        'forestgreen' => '34,139,34',
+        'fuchsia' => '255,0,255',
+        'gainsboro' => '220,220,220',
+        'ghostwhite' => '248,248,255',
+        'gold' => '255,215,0',
+        'goldenrod' => '218,165,32',
+        'gray' => '128,128,128',
+        'green' => '0,128,0',
+        'greenyellow' => '173,255,47',
+        'grey' => '128,128,128',
+        'honeydew' => '240,255,240',
+        'hotpink' => '255,105,180',
+        'indianred' => '205,92,92',
+        'indigo' => '75,0,130',
+        'ivory' => '255,255,240',
+        'khaki' => '240,230,140',
+        'lavender' => '230,230,250',
+        'lavenderblush' => '255,240,245',
+        'lawngreen' => '124,252,0',
+        'lemonchiffon' => '255,250,205',
+        'lightblue' => '173,216,230',
+        'lightcoral' => '240,128,128',
+        'lightcyan' => '224,255,255',
+        'lightgoldenrodyellow' => '250,250,210',
+        'lightgray' => '211,211,211',
+        'lightgreen' => '144,238,144',
+        'lightgrey' => '211,211,211',
+        'lightpink' => '255,182,193',
+        'lightsalmon' => '255,160,122',
+        'lightseagreen' => '32,178,170',
+        'lightskyblue' => '135,206,250',
+        'lightslategray' => '119,136,153',
+        'lightslategrey' => '119,136,153',
+        'lightsteelblue' => '176,196,222',
+        'lightyellow' => '255,255,224',
+        'lime' => '0,255,0',
+        'limegreen' => '50,205,50',
+        'linen' => '250,240,230',
+        'magenta' => '255,0,255',
+        'maroon' => '128,0,0',
+        'mediumaquamarine' => '102,205,170',
+        'mediumblue' => '0,0,205',
+        'mediumorchid' => '186,85,211',
+        'mediumpurple' => '147,112,219',
+        'mediumseagreen' => '60,179,113',
+        'mediumslateblue' => '123,104,238',
+        'mediumspringgreen' => '0,250,154',
+        'mediumturquoise' => '72,209,204',
+        'mediumvioletred' => '199,21,133',
+        'midnightblue' => '25,25,112',
+        'mintcream' => '245,255,250',
+        'mistyrose' => '255,228,225',
+        'moccasin' => '255,228,181',
+        'navajowhite' => '255,222,173',
+        'navy' => '0,0,128',
+        'oldlace' => '253,245,230',
+        'olive' => '128,128,0',
+        'olivedrab' => '107,142,35',
+        'orange' => '255,165,0',
+        'orangered' => '255,69,0',
+        'orchid' => '218,112,214',
+        'palegoldenrod' => '238,232,170',
+        'palegreen' => '152,251,152',
+        'paleturquoise' => '175,238,238',
+        'palevioletred' => '219,112,147',
+        'papayawhip' => '255,239,213',
+        'peachpuff' => '255,218,185',
+        'peru' => '205,133,63',
+        'pink' => '255,192,203',
+        'plum' => '221,160,221',
+        'powderblue' => '176,224,230',
+        'purple' => '128,0,128',
+        'red' => '255,0,0',
+        'rosybrown' => '188,143,143',
+        'royalblue' => '65,105,225',
+        'saddlebrown' => '139,69,19',
+        'salmon' => '250,128,114',
+        'sandybrown' => '244,164,96',
+        'seagreen' => '46,139,87',
+        'seashell' => '255,245,238',
+        'sienna' => '160,82,45',
+        'silver' => '192,192,192',
+        'skyblue' => '135,206,235',
+        'slateblue' => '106,90,205',
+        'slategray' => '112,128,144',
+        'slategrey' => '112,128,144',
+        'snow' => '255,250,250',
+        'springgreen' => '0,255,127',
+        'steelblue' => '70,130,180',
+        'tan' => '210,180,140',
+        'teal' => '0,128,128',
+        'thistle' => '216,191,216',
+        'tomato' => '255,99,71',
+        'transparent' => '0,0,0,0',
+        'turquoise' => '64,224,208',
+        'violet' => '238,130,238',
+        'wheat' => '245,222,179',
+        'white' => '255,255,255',
+        'whitesmoke' => '245,245,245',
+        'yellow' => '255,255,0',
+        'yellowgreen' => '154,205,50'
+    );
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Compiler.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Compiler.php
new file mode 100644
index 0000000000..bef345bc6c
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Compiler.php
@@ -0,0 +1,4457 @@
+
+ */
+class Compiler
+{
+    const LINE_COMMENTS = 1;
+    const DEBUG_INFO    = 2;
+
+    /**
+     * @var array
+     */
+    static protected $operatorNames = array(
+        '+' => 'add',
+        '-' => 'sub',
+        '*' => 'mul',
+        '/' => 'div',
+        '%' => 'mod',
+
+        '==' => 'eq',
+        '!=' => 'neq',
+        '<' => 'lt',
+        '>' => 'gt',
+
+        '<=' => 'lte',
+        '>=' => 'gte',
+    );
+
+    /**
+     * @var array
+     */
+    static protected $namespaces = array(
+        'special' => '%',
+        'mixin' => '@',
+        'function' => '^',
+    );
+
+    /**
+     * @var array
+     */
+    static protected $unitTable = array(
+        'in' => array(
+            'in' => 1,
+            'pt' => 72,
+            'pc' => 6,
+            'cm' => 2.54,
+            'mm' => 25.4,
+            'px' => 96,
+            'q'  => 101.6,
+        )
+    );
+
+    static public $true = array('keyword', 'true');
+    static public $false = array('keyword', 'false');
+    static public $null = array('null');
+    static public $defaultValue = array('keyword', '');
+    static public $selfSelector = array('self');
+    static public $emptyList = array('list', '', array());
+    static public $emptyMap = array('map', array(), array());
+    static public $emptyString = array('string', '"', array());
+
+    protected $importPaths = array('');
+    protected $importCache = array();
+    protected $userFunctions = array();
+    protected $registeredVars = array();
+
+    protected $numberPrecision = 5;
+    protected $lineNumberStyle = null;
+
+    protected $formatter = 'Leafo\ScssPhp\Formatter\Nested';
+
+    private $indentLevel;
+    private $commentsSeen;
+    private $extends;
+    private $extendsMap;
+    private $parsedFiles;
+    private $env;
+    private $scope;
+    private $parser;
+    private $sourcePos;
+    private $sourceParser;
+    private $storeEnv;
+    private $charsetSeen;
+    private $stderr;
+    private $shouldEvaluate;
+
+    /**
+     * Compile scss
+     *
+     * @api
+     *
+     * @param string $code
+     * @param string $name
+     *
+     * @return string
+     */
+    public function compile($code, $name = null)
+    {
+        $this->indentLevel  = -1;
+        $this->commentsSeen = array();
+        $this->extends      = array();
+        $this->extendsMap   = array();
+        $this->parsedFiles  = array();
+        $this->env          = null;
+        $this->scope        = null;
+
+        $this->stderr = fopen('php://stderr', 'w');
+
+        $locale = setlocale(LC_NUMERIC, 0);
+        setlocale(LC_NUMERIC, 'C');
+
+        $this->parser = new Parser($name);
+
+        $tree = $this->parser->parse($code);
+
+        $this->formatter = new $this->formatter();
+
+        $this->rootEnv = $this->pushEnv($tree);
+        $this->injectVariables($this->registeredVars);
+        $this->compileRoot($tree);
+        $this->popEnv();
+
+        $out = $this->formatter->format($this->scope);
+
+        setlocale(LC_NUMERIC, $locale);
+
+        return $out;
+    }
+
+    /**
+     * Is self extend?
+     *
+     * @param array $target
+     * @param array $origin
+     *
+     * @return boolean
+     */
+    protected function isSelfExtend($target, $origin)
+    {
+        foreach ($origin as $sel) {
+            if (in_array($target, $sel)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Push extends
+     *
+     * @param array $target
+     * @param array $origin
+     */
+    protected function pushExtends($target, $origin)
+    {
+        if ($this->isSelfExtend($target, $origin)) {
+            return;
+        }
+
+        $i = count($this->extends);
+        $this->extends[] = array($target, $origin);
+
+        foreach ($target as $part) {
+            if (isset($this->extendsMap[$part])) {
+                $this->extendsMap[$part][] = $i;
+            } else {
+                $this->extendsMap[$part] = array($i);
+            }
+        }
+    }
+
+    /**
+     * Make output block
+     *
+     * @param string $type
+     * @param array  $selectors
+     *
+     * @return \stdClass
+     */
+    protected function makeOutputBlock($type, $selectors = null)
+    {
+        $out = new \stdClass;
+        $out->type = $type;
+        $out->lines = array();
+        $out->children = array();
+        $out->parent = $this->scope;
+        $out->selectors = $selectors;
+        $out->depth = $this->env->depth;
+
+        return $out;
+    }
+
+    /**
+     * Compile root
+     *
+     * @param \stdClass $rootBlock
+     */
+    protected function compileRoot($rootBlock)
+    {
+        $this->scope = $this->makeOutputBlock('root');
+
+        $this->compileChildren($rootBlock->children, $this->scope);
+        $this->flattenSelectors($this->scope);
+    }
+
+    /**
+     * Flatten selectors
+     *
+     * @param \stdClass $block
+     * @parent string   $parentKey
+     */
+    protected function flattenSelectors($block, $parentKey = null)
+    {
+        if ($block->selectors) {
+            $selectors = array();
+
+            foreach ($block->selectors as $s) {
+                $selectors[] = $s;
+
+                if (! is_array($s)) {
+                    continue;
+                }
+
+                // check extends
+                if (! empty($this->extendsMap)) {
+                    $this->matchExtends($s, $selectors);
+
+                    // remove duplicates
+                    array_walk($selectors, function (&$value) {
+                        $value = json_encode($value);
+                    });
+                    $selectors = array_unique($selectors);
+                    array_walk($selectors, function (&$value) {
+                        $value = json_decode($value);
+                    });
+                }
+            }
+
+            $block->selectors = array();
+            $placeholderSelector = false;
+
+            foreach ($selectors as $selector) {
+                if ($this->hasSelectorPlaceholder($selector)) {
+                    $placeholderSelector = true;
+                    continue;
+                }
+
+                $block->selectors[] = $this->compileSelector($selector);
+            }
+
+            if ($placeholderSelector && 0 === count($block->selectors) && null !== $parentKey) {
+                unset($block->parent->children[$parentKey]);
+
+                return;
+            }
+        }
+
+        foreach ($block->children as $key => $child) {
+            $this->flattenSelectors($child, $key);
+        }
+    }
+
+    /**
+     * Match extends
+     *
+     * @param array   $selector
+     * @param array   $out
+     * @param integer $from
+     * @param boolean $initial
+     */
+    protected function matchExtends($selector, &$out, $from = 0, $initial = true)
+    {
+        foreach ($selector as $i => $part) {
+            if ($i < $from) {
+                continue;
+            }
+
+            if ($this->matchExtendsSingle($part, $origin)) {
+                $before = array_slice($selector, 0, $i);
+                $after = array_slice($selector, $i + 1);
+                $s = count($before);
+
+                foreach ($origin as $new) {
+                    $k = 0;
+
+                    // remove shared parts
+                    if ($initial) {
+                        while ($k < $s && isset($new[$k]) && $before[$k] === $new[$k]) {
+                            $k++;
+                        }
+                    }
+
+                    $result = array_merge(
+                        $before,
+                        $k > 0 ? array_slice($new, $k) : $new,
+                        $after
+                    );
+
+                    if ($result === $selector) {
+                        continue;
+                    }
+
+                    $out[] = $result;
+
+                    // recursively check for more matches
+                    $this->matchExtends($result, $out, $i, false);
+
+                    // selector sequence merging
+                    if (! empty($before) && count($new) > 1) {
+                        $result2 = array_merge(
+                            array_slice($new, 0, -1),
+                            $k > 0 ? array_slice($before, $k) : $before,
+                            array_slice($new, -1),
+                            $after
+                        );
+
+                        $out[] = $result2;
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Match extends single
+     *
+     * @param array $rawSingle
+     * @param array $outOrigin
+     *
+     * @return boolean
+     */
+    protected function matchExtendsSingle($rawSingle, &$outOrigin)
+    {
+        $counts = array();
+        $single = array();
+
+        foreach ($rawSingle as $part) {
+            // matches Number
+            if (! is_string($part)) {
+                return false;
+            }
+
+            if (! preg_match('/^[\[.:#%]/', $part) && count($single)) {
+                $single[count($single) - 1] .= $part;
+            } else {
+                $single[] = $part;
+            }
+        }
+
+        foreach ($single as $part) {
+            if (isset($this->extendsMap[$part])) {
+                foreach ($this->extendsMap[$part] as $idx) {
+                    $counts[$idx] = isset($counts[$idx]) ? $counts[$idx] + 1 : 1;
+                }
+            }
+        }
+
+        $outOrigin = array();
+        $found = false;
+
+        foreach ($counts as $idx => $count) {
+            list($target, $origin) = $this->extends[$idx];
+
+            // check count
+            if ($count !== count($target)) {
+                continue;
+            }
+
+            $rem = array_diff($single, $target);
+
+            foreach ($origin as $j => $new) {
+                // prevent infinite loop when target extends itself
+                if ($this->isSelfExtend($single, $origin)) {
+                    return false;
+                }
+
+                $origin[$j][count($origin[$j]) - 1] = $this->combineSelectorSingle(end($new), $rem);
+            }
+
+            $outOrigin = array_merge($outOrigin, $origin);
+
+            $found = true;
+        }
+
+        return $found;
+    }
+
+    /**
+     * Combine selector single
+     *
+     * @param array $base
+     * @param array $other
+     *
+     * @return array
+     */
+    protected function combineSelectorSingle($base, $other)
+    {
+        $tag = null;
+        $out = array();
+
+        foreach (array($base, $other) as $single) {
+            foreach ($single as $part) {
+                if (preg_match('/^[^\[.#:]/', $part)) {
+                    $tag = $part;
+                } else {
+                    $out[] = $part;
+                }
+            }
+        }
+
+        if ($tag) {
+            array_unshift($out, $tag);
+        }
+
+        return $out;
+    }
+
+    /**
+     * Compile media
+     *
+     * @param \stdClass $media
+     */
+    protected function compileMedia($media)
+    {
+        $this->pushEnv($media);
+
+        $mediaQuery = $this->compileMediaQuery($this->multiplyMedia($this->env));
+
+        if (! empty($mediaQuery)) {
+            $this->scope = $this->makeOutputBlock('media', array($mediaQuery));
+
+            $parentScope = $this->mediaParent($this->scope);
+            $parentScope->children[] = $this->scope;
+
+            // top level properties in a media cause it to be wrapped
+            $needsWrap = false;
+
+            foreach ($media->children as $child) {
+                $type = $child[0];
+
+                if ($type !== 'block' && $type !== 'media' && $type !== 'directive') {
+                    $needsWrap = true;
+                    break;
+                }
+            }
+
+            if ($needsWrap) {
+                $wrapped = (object)array(
+                    'selectors' => array(),
+                    'children' => $media->children
+                );
+                $media->children = array(array('block', $wrapped));
+            }
+
+            $this->compileChildren($media->children, $this->scope);
+
+            $this->scope = $this->scope->parent;
+        }
+
+        $this->popEnv();
+    }
+
+    /**
+     * Media parent
+     *
+     * @param \stdClass $scope
+     *
+     * @return \stdClass
+     */
+    protected function mediaParent($scope)
+    {
+        while (! empty($scope->parent)) {
+            if (! empty($scope->type) && $scope->type !== 'media') {
+                break;
+            }
+
+            $scope = $scope->parent;
+        }
+
+        return $scope;
+    }
+
+    /**
+     * Compile nested block
+     *
+     * @todo refactor compileNestedBlock and compileMedia into same thing?
+     *
+     * @param \stdClass $block
+     * @param array     $selectors
+     */
+    protected function compileNestedBlock($block, $selectors)
+    {
+        $this->pushEnv($block);
+
+        $this->scope = $this->makeOutputBlock($block->type, $selectors);
+        $this->scope->parent->children[] = $this->scope;
+
+        $this->compileChildren($block->children, $this->scope);
+
+        $this->scope = $this->scope->parent;
+
+        $this->popEnv();
+    }
+
+    /**
+     * Recursively compiles a block.
+     *
+     * A block is analogous to a CSS block in most cases. A single SCSS document
+     * is encapsulated in a block when parsed, but it does not have parent tags
+     * so all of its children appear on the root level when compiled.
+     *
+     * Blocks are made up of selectors and children.
+     *
+     * The children of a block are just all the blocks that are defined within.
+     *
+     * Compiling the block involves pushing a fresh environment on the stack,
+     * and iterating through the props, compiling each one.
+     *
+     * @see Compiler::compileChild()
+     *
+     * @param \stdClass $block
+     */
+    protected function compileBlock($block)
+    {
+        $env = $this->pushEnv($block);
+
+        $env->selectors = $this->evalSelectors($block->selectors);
+
+        $out = $this->makeOutputBlock(null, $this->multiplySelectors($env));
+
+        if (isset($this->lineNumberStyle) && count($env->selectors) && count($block->children)) {
+            $annotation = $this->makeOutputBlock('comment');
+            $annotation->depth = 0;
+
+            $file = $block->sourceParser->getSourceName();
+            $line = $block->sourceParser->getLineNo($block->sourcePosition);
+
+            switch ($this->lineNumberStyle) {
+                case self::LINE_COMMENTS:
+                    $annotation->lines[] = '/* line ' . $line . ', ' . $file . ' */';
+                    break;
+
+                case self::DEBUG_INFO:
+                    $annotation->lines[] = '@media -sass-debug-info{filename{font-family:"' . $file
+                                         . '"}line{font-family:' . $line . '}}';
+                    break;
+            }
+
+            $this->scope->children[] = $annotation;
+        }
+
+        $this->scope->children[] = $out;
+
+        $this->compileChildren($block->children, $out);
+
+        $this->formatter->stripSemicolon($out->lines);
+
+        $this->popEnv();
+    }
+
+    /**
+     * Compile root level comment
+     *
+     * @param array $block
+     */
+    protected function compileComment($block)
+    {
+        $out = $this->makeOutputBlock('comment');
+        $out->lines[] = $block[1];
+        $this->scope->children[] = $out;
+    }
+
+    /**
+     * Evaluate selectors
+     *
+     * @param array $selectors
+     *
+     * @return array
+     */
+    protected function evalSelectors($selectors)
+    {
+        $this->shouldEvaluate = false;
+
+        $selectors = array_map(array($this, 'evalSelector'), $selectors);
+
+        // after evaluating interpolates, we might need a second pass
+        if ($this->shouldEvaluate) {
+            $buffer = $this->collapseSelectors($selectors);
+            $parser = new Parser(__METHOD__, false);
+
+            if ($parser->parseSelector($buffer, $newSelectors)) {
+                $selectors = array_map(array($this, 'evalSelector'), $newSelectors);
+            }
+        }
+
+        return $selectors;
+    }
+
+    /**
+     * Evaluate selector
+     *
+     * @param array $selector
+     *
+     * @return array
+     */
+    protected function evalSelector($selector)
+    {
+        return array_map(array($this, 'evalSelectorPart'), $selector);
+    }
+
+    /**
+     * Evaluate selector part; replaces all the interpolates, stripping quotes
+     *
+     * @param array $part
+     *
+     * @return array
+     */
+    protected function evalSelectorPart($part)
+    {
+        foreach ($part as &$p) {
+            if (is_array($p) && ($p[0] === 'interpolate' || $p[0] === 'string')) {
+                $p = $this->compileValue($p);
+
+                // force re-evaluation
+                if (strpos($p, '&') !== false || strpos($p, ',') !== false) {
+                    $this->shouldEvaluate = true;
+                }
+            } elseif (is_string($p) && strlen($p) >= 2 &&
+                ($first = $p[0]) && ($first === '"' || $first === "'") &&
+                substr($p, -1) === $first
+            ) {
+                $p = substr($p, 1, -1);
+            }
+        }
+
+        return $this->flattenSelectorSingle($part);
+    }
+
+    /**
+     * Collapse selectors
+     *
+     * @param array $selectors
+     *
+     * @return string
+     */
+    protected function collapseSelectors($selectors)
+    {
+        $parts = array();
+
+        foreach ($selectors as $selector) {
+            $output = '';
+
+            array_walk_recursive(
+                $selector,
+                function ($value, $key) use (&$output) {
+                    $output .= $value;
+                }
+            );
+
+            $parts[] = $output;
+        }
+
+        return implode(', ', $parts);
+    }
+
+    /**
+     * Flatten selector single; joins together .classes and #ids
+     *
+     * @param array $single
+     *
+     * @return array
+     */
+    protected function flattenSelectorSingle($single)
+    {
+        $joined = array();
+
+        foreach ($single as $part) {
+            if (empty($joined) ||
+                ! is_string($part) ||
+                preg_match('/[\[.:#%]/', $part)
+            ) {
+                $joined[] = $part;
+                continue;
+            }
+
+            if (is_array(end($joined))) {
+                $joined[] = $part;
+            } else {
+                $joined[count($joined) - 1] .= $part;
+            }
+        }
+
+        return $joined;
+    }
+
+    /**
+     * Compile selector to string; self(&) should have been replaced by now
+     *
+     * @param array $selector
+     *
+     * @return string
+     */
+    protected function compileSelector($selector)
+    {
+        if (! is_array($selector)) {
+            return $selector; // media and the like
+        }
+
+        return implode(
+            ' ',
+            array_map(
+                array($this, 'compileSelectorPart'),
+                $selector
+            )
+        );
+    }
+
+    /**
+     * Compile selector part
+     *
+     * @param arary $piece
+     *
+     * @return string
+     */
+    protected function compileSelectorPart($piece)
+    {
+        foreach ($piece as &$p) {
+            if (! is_array($p)) {
+                continue;
+            }
+
+            switch ($p[0]) {
+                case 'self':
+                    $p = '&';
+                    break;
+
+                default:
+                    $p = $this->compileValue($p);
+                    break;
+            }
+        }
+
+        return implode($piece);
+    }
+
+    /**
+     * Has selector placeholder?
+     *
+     * @param array $selector
+     *
+     * @return boolean
+     */
+    protected function hasSelectorPlaceholder($selector)
+    {
+        if (! is_array($selector)) {
+            return false;
+        }
+
+        foreach ($selector as $parts) {
+            foreach ($parts as $part) {
+                if ('%' === $part[0]) {
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Compile children
+     *
+     * @param array $stms
+     * @param array $out
+     *
+     * @return array
+     */
+    protected function compileChildren($stms, $out)
+    {
+        foreach ($stms as $stm) {
+            $ret = $this->compileChild($stm, $out);
+
+            if (isset($ret)) {
+                return $ret;
+            }
+        }
+    }
+
+    /**
+     * Compile media query
+     *
+     * @param array $queryList
+     *
+     * @return string
+     */
+    protected function compileMediaQuery($queryList)
+    {
+        $out = '@media';
+        $first = true;
+
+        foreach ($queryList as $query) {
+            $type = null;
+            $parts = array();
+
+            foreach ($query as $q) {
+                switch ($q[0]) {
+                    case 'mediaType':
+                        if ($type) {
+                            $type = $this->mergeMediaTypes(
+                                $type,
+                                array_map(array($this, 'compileValue'), array_slice($q, 1))
+                            );
+
+                            if (empty($type)) { // merge failed
+                                return null;
+                            }
+                        } else {
+                            $type = array_map(array($this, 'compileValue'), array_slice($q, 1));
+                        }
+                        break;
+
+                    case 'mediaExp':
+                        if (isset($q[2])) {
+                            $parts[] = '('
+                                . $this->compileValue($q[1])
+                                . $this->formatter->assignSeparator
+                                . $this->compileValue($q[2])
+                                . ')';
+                        } else {
+                            $parts[] = '('
+                                . $this->compileValue($q[1])
+                                . ')';
+                        }
+                        break;
+                }
+            }
+
+            if ($type) {
+                array_unshift($parts, implode(' ', array_filter($type)));
+            }
+
+            if (! empty($parts)) {
+                if ($first) {
+                    $first = false;
+                    $out .= ' ';
+                } else {
+                    $out .= $this->formatter->tagSeparator;
+                }
+
+                $out .= implode(' and ', $parts);
+            }
+        }
+
+        return $out;
+    }
+
+    /**
+     * Merge media types
+     *
+     * @param array $type1
+     * @param array $type2
+     *
+     * @return array|null
+     */
+    protected function mergeMediaTypes($type1, $type2)
+    {
+        if (empty($type1)) {
+            return $type2;
+        }
+
+        if (empty($type2)) {
+            return $type1;
+        }
+
+        $m1 = '';
+        $t1 = '';
+
+        if (count($type1) > 1) {
+            $m1= strtolower($type1[0]);
+            $t1= strtolower($type1[1]);
+        } else {
+            $t1 = strtolower($type1[0]);
+        }
+
+        $m2 = '';
+        $t2 = '';
+
+        if (count($type2) > 1) {
+            $m2 = strtolower($type2[0]);
+            $t2 = strtolower($type2[1]);
+        } else {
+            $t2 = strtolower($type2[0]);
+        }
+
+        if (($m1 === 'not') ^ ($m2 === 'not')) {
+            if ($t1 === $t2) {
+                return null;
+            }
+
+            return array(
+                $m1 === 'not' ? $m2 : $m1,
+                $m1 === 'not' ? $t2 : $t1
+            );
+        }
+
+        if ($m1 === 'not' && $m2 === 'not') {
+            // CSS has no way of representing "neither screen nor print"
+            if ($t1 !== $t2) {
+                return null;
+            }
+
+            return array('not', $t1);
+        }
+
+        if ($t1 !== $t2) {
+            return null;
+        }
+
+        // t1 == t2, neither m1 nor m2 are "not"
+        return array(empty($m1)? $m2 : $m1, $t1);
+    }
+
+    /**
+     * Compile import; returns true if the value was something that could be imported
+     *
+     * @param array $rawPath
+     * @param array $out
+     *
+     * @return boolean
+     */
+    protected function compileImport($rawPath, $out)
+    {
+        if ($rawPath[0] === 'string') {
+            $path = $this->compileStringContent($rawPath);
+
+            if ($path = $this->findImport($path)) {
+                $this->importFile($path, $out);
+
+                return true;
+            }
+
+            return false;
+        }
+
+        if ($rawPath[0] === 'list') {
+            // handle a list of strings
+            if (count($rawPath[2]) === 0) {
+                return false;
+            }
+
+            foreach ($rawPath[2] as $path) {
+                if ($path[0] !== 'string') {
+                    return false;
+                }
+            }
+
+            foreach ($rawPath[2] as $path) {
+                $this->compileImport($path, $out);
+            }
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Compile child; returns a value to halt execution
+     *
+     * @param array     $child
+     * @param \stdClass $out
+     *
+     * @return array
+     */
+    protected function compileChild($child, $out)
+    {
+        $this->sourcePos = isset($child[Parser::SOURCE_POSITION]) ? $child[Parser::SOURCE_POSITION] : -1;
+        $this->sourceParser = isset($child[Parser::SOURCE_PARSER]) ? $child[Parser::SOURCE_PARSER] : $this->parser;
+
+        switch ($child[0]) {
+            case 'import':
+                list(, $rawPath) = $child;
+
+                $rawPath = $this->reduce($rawPath);
+
+                if (! $this->compileImport($rawPath, $out)) {
+                    $out->lines[] = '@import ' . $this->compileValue($rawPath) . ';';
+                }
+                break;
+
+            case 'directive':
+                list(, $directive) = $child;
+
+                $s = '@' . $directive->name;
+
+                if (! empty($directive->value)) {
+                    $s .= ' ' . $this->compileValue($directive->value);
+                }
+
+                $this->compileNestedBlock($directive, array($s));
+                break;
+
+            case 'media':
+                $this->compileMedia($child[1]);
+                break;
+
+            case 'block':
+                $this->compileBlock($child[1]);
+                break;
+
+            case 'charset':
+                if (! $this->charsetSeen) {
+                    $this->charsetSeen = true;
+
+                    $out->lines[] = '@charset ' . $this->compileValue($child[1]) . ';';
+                }
+                break;
+
+            case 'assign':
+                list(, $name, $value) = $child;
+
+                if ($name[0] === 'var') {
+                    $flag = isset($child[3]) ? $child[3] : null;
+                    $isDefault = $flag === '!default';
+                    $isGlobal = $flag === '!global';
+
+                    if ($isGlobal) {
+                        $this->set($name[1], $this->reduce($value), false, $this->rootEnv);
+                        break;
+                    }
+
+                    $shouldSet = $isDefault &&
+                        (($result = $this->get($name[1], false)) === null
+                        || $result === self::$null);
+
+                    if (! $isDefault || $shouldSet) {
+                        $this->set($name[1], $this->reduce($value));
+                    }
+                    break;
+                }
+
+                $compiledName = $this->compileValue($name);
+
+                // handle shorthand syntax: size / line-height
+                if ($compiledName === 'font') {
+                    if ($value[0] === 'exp' && $value[1] === '/') {
+                        $value = $this->expToString($value);
+                    } elseif ($value[0] === 'list') {
+                        foreach ($value[2] as &$item) {
+                            if ($item[0] === 'exp' && $item[1] === '/') {
+                                $item = $this->expToString($item);
+                            }
+                        }
+                    }
+                }
+
+                // if the value reduces to null from something else then
+                // the property should be discarded
+                if ($value[0] !== 'null') {
+                    $value = $this->reduce($value);
+
+                    if ($value[0] === 'null') {
+                        break;
+                    }
+                }
+
+                $compiledValue = $this->compileValue($value);
+
+                $out->lines[] = $this->formatter->property(
+                    $compiledName,
+                    $compiledValue
+                );
+                break;
+
+            case 'comment':
+                if ($out->type === 'root') {
+                    $this->compileComment($child);
+                    break;
+                }
+
+                $out->lines[] = $child[1];
+                break;
+
+            case 'mixin':
+            case 'function':
+                list(, $block) = $child;
+
+                $this->set(self::$namespaces[$block->type] . $block->name, $block);
+                break;
+
+            case 'extend':
+                list(, $selectors) = $child;
+
+                foreach ($selectors as $sel) {
+                    // only use the first one
+                    $result = $this->evalSelectors(array($sel));
+                    $result = current($result[0]);
+
+                    $this->pushExtends($result, $out->selectors);
+                }
+                break;
+
+            case 'if':
+                list(, $if) = $child;
+
+                if ($this->isTruthy($this->reduce($if->cond, true))) {
+                    return $this->compileChildren($if->children, $out);
+                }
+
+                foreach ($if->cases as $case) {
+                    if ($case->type === 'else' ||
+                        $case->type === 'elseif' && $this->isTruthy($this->reduce($case->cond))
+                    ) {
+                        return $this->compileChildren($case->children, $out);
+                    }
+                }
+                break;
+
+            case 'return':
+                return $this->reduce($child[1], true);
+
+            case 'each':
+                list(, $each) = $child;
+
+                $list = $this->coerceList($this->reduce($each->list));
+
+                $this->pushEnv();
+
+                foreach ($list[2] as $item) {
+                    if (count($each->vars) === 1) {
+                        $this->set($each->vars[0], $item, true);
+                    } else {
+                        list(,, $values) = $this->coerceList($item);
+
+                        foreach ($each->vars as $i => $var) {
+                            $this->set($var, isset($values[$i]) ? $values[$i] : self::$null, true);
+                        }
+                    }
+
+                    $ret = $this->compileChildren($each->children, $out);
+
+                    if ($ret) {
+                        $this->popEnv();
+
+                        return $ret;
+                    }
+                }
+
+                $this->popEnv();
+                break;
+
+            case 'while':
+                list(, $while) = $child;
+
+                while ($this->isTruthy($this->reduce($while->cond, true))) {
+                    $ret = $this->compileChildren($while->children, $out);
+
+                    if ($ret) {
+                        return $ret;
+                    }
+                }
+                break;
+
+            case 'for':
+                list(, $for) = $child;
+
+                $start = $this->reduce($for->start, true);
+                $start = $start[1];
+                $end = $this->reduce($for->end, true);
+                $end = $end[1];
+                $d = $start < $end ? 1 : -1;
+
+                while (true) {
+                    if ((! $for->until && $start - $d == $end) ||
+                        ($for->until && $start == $end)
+                    ) {
+                        break;
+                    }
+
+                    $this->set($for->var, array('number', $start, ''));
+                    $start += $d;
+
+                    $ret = $this->compileChildren($for->children, $out);
+
+                    if ($ret) {
+                        return $ret;
+                    }
+                }
+                break;
+
+            case 'nestedprop':
+                list(, $prop) = $child;
+
+                $prefixed = array();
+                $prefix = $this->compileValue($prop->prefix) . '-';
+
+                foreach ($prop->children as $child) {
+                    if ($child[0] === 'assign') {
+                        array_unshift($child[1][2], $prefix);
+                    }
+
+                    if ($child[0] === 'nestedprop') {
+                        array_unshift($child[1]->prefix[2], $prefix);
+                    }
+
+                    $prefixed[] = $child;
+                }
+
+                $this->compileChildren($prefixed, $out);
+                break;
+
+            case 'include':
+                // including a mixin
+                list(, $name, $argValues, $content) = $child;
+
+                $mixin = $this->get(self::$namespaces['mixin'] . $name, false);
+
+                if (! $mixin) {
+                    $this->throwError("Undefined mixin $name");
+                }
+
+                $callingScope = $this->env;
+
+                // push scope, apply args
+                $this->pushEnv();
+                $this->env->depth--;
+
+                if (isset($content)) {
+                    $content->scope = $callingScope;
+
+                    $this->setRaw(self::$namespaces['special'] . 'content', $content);
+                }
+
+                if (isset($mixin->args)) {
+                    $this->applyArguments($mixin->args, $argValues);
+                }
+
+                $this->env->marker = 'mixin';
+
+                foreach ($mixin->children as $child) {
+                    $this->compileChild($child, $out);
+                }
+
+                $this->popEnv();
+                break;
+
+            case 'mixin_content':
+                $content = $this->get(self::$namespaces['special'] . 'content', false);
+
+                if (! $content) {
+                    $this->throwError('Expected @content inside of mixin');
+                }
+
+                if (! isset($content->children)) {
+                    break;
+                }
+
+                $this->storeEnv = $content->scope;
+
+                foreach ($content->children as $child) {
+                    $this->compileChild($child, $out);
+                }
+
+                $this->storeEnv = null;
+
+                break;
+
+            case 'debug':
+                list(, $value) = $child;
+
+                $line = $this->parser->getLineNo($this->sourcePos);
+                $value = $this->compileValue($this->reduce($value, true));
+                fwrite($this->stderr, "Line $line DEBUG: $value\n");
+                break;
+
+            case 'warn':
+                list(, $value) = $child;
+
+                $line = $this->parser->getLineNo($this->sourcePos);
+                $value = $this->compileValue($this->reduce($value, true));
+                echo "Line $line WARN: $value\n";
+                break;
+
+            case 'error':
+                list(, $value) = $child;
+
+                $line = $this->parser->getLineNo($this->sourcePos);
+                $value = $this->compileValue($this->reduce($value, true));
+                $this->throwError("Line $line ERROR: $value\n");
+                break;
+
+            default:
+                $this->throwError("unknown child type: $child[0]");
+        }
+    }
+
+    /**
+     * Reduce expression to string
+     *
+     * @param array $exp
+     *
+     * @return array
+     */
+    protected function expToString($exp)
+    {
+        list(, $op, $left, $right, $inParens, $whiteLeft, $whiteRight) = $exp;
+
+        $content = array($this->reduce($left));
+
+        if ($whiteLeft) {
+            $content[] = ' ';
+        }
+
+        $content[] = $op;
+
+        if ($whiteRight) {
+            $content[] = ' ';
+        }
+
+        $content[] = $this->reduce($right);
+
+        return array('string', '', $content);
+    }
+
+    /**
+     * Is truthy?
+     *
+     * @param array $value
+     *
+     * @return array
+     */
+    protected function isTruthy($value)
+    {
+        return $value !== self::$false && $value !== self::$null;
+    }
+
+    /**
+     * Should $value cause its operand to eval
+     *
+     * @param array $value
+     *
+     * @return boolean
+     */
+    protected function shouldEval($value)
+    {
+        switch ($value[0]) {
+            case 'exp':
+                if ($value[1] === '/') {
+                    return $this->shouldEval($value[2], $value[3]);
+                }
+
+                // fall-thru
+            case 'var':
+            case 'fncall':
+                return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Reduce value
+     *
+     * @param array   $value
+     * @param boolean $inExp
+     *
+     * @return array
+     */
+    protected function reduce($value, $inExp = false)
+    {
+        list($type) = $value;
+
+        switch ($type) {
+            case 'exp':
+                list(, $op, $left, $right, $inParens) = $value;
+
+                $opName = isset(self::$operatorNames[$op]) ? self::$operatorNames[$op] : $op;
+                $inExp = $inExp || $this->shouldEval($left) || $this->shouldEval($right);
+
+                $left = $this->reduce($left, true);
+                $right = $this->reduce($right, true);
+
+                // special case: looks like css short-hand
+                if ($opName === 'div' && ! $inParens && ! $inExp && isset($right[2]) && $right[2] !== '') {
+                    return $this->expToString($value);
+                }
+
+                $left = $this->coerceForExpression($left);
+                $right = $this->coerceForExpression($right);
+
+                $ltype = $left[0];
+                $rtype = $right[0];
+
+                $ucOpName = ucfirst($opName);
+                $ucLType  = ucfirst($ltype);
+                $ucRType  = ucfirst($rtype);
+
+                // this tries:
+                // 1. op[op name][left type][right type]
+                // 2. op[left type][right type] (passing the op as first arg
+                // 3. op[op name]
+                $fn = "op${ucOpName}${ucLType}${ucRType}";
+
+                if (is_callable(array($this, $fn)) ||
+                    (($fn = "op${ucLType}${ucRType}") &&
+                        is_callable(array($this, $fn)) &&
+                        $passOp = true) ||
+                    (($fn = "op${ucOpName}") &&
+                        is_callable(array($this, $fn)) &&
+                        $genOp = true)
+                ) {
+                    $unitChange = false;
+
+                    if (! isset($genOp) &&
+                        $left[0] === 'number' && $right[0] === 'number'
+                    ) {
+                        if ($opName === 'mod' && $right[2] !== '') {
+                            $this->throwError("Cannot modulo by a number with units: $right[1]$right[2].");
+                        }
+
+                        $unitChange = true;
+                        $emptyUnit = $left[2] === '' || $right[2] === '';
+                        $targetUnit = '' !== $left[2] ? $left[2] : $right[2];
+
+                        if ($opName !== 'mul') {
+                            $left[2] = '' !== $left[2] ? $left[2] : $targetUnit;
+                            $right[2] = '' !== $right[2] ? $right[2] : $targetUnit;
+                        }
+
+                        if ($opName !== 'mod') {
+                            $left = $this->normalizeNumber($left);
+                            $right = $this->normalizeNumber($right);
+                        }
+
+                        if ($opName === 'div' && ! $emptyUnit && $left[2] === $right[2]) {
+                            $targetUnit = '';
+                        }
+
+                        if ($opName === 'mul') {
+                            $left[2] = '' !== $left[2] ? $left[2] : $right[2];
+                            $right[2] = '' !== $right[2] ? $right[2] : $left[2];
+                        } elseif ($opName === 'div' && $left[2] === $right[2]) {
+                            $left[2] = '';
+                            $right[2] = '';
+                        }
+                    }
+
+                    $shouldEval = $inParens || $inExp;
+
+                    if (isset($passOp)) {
+                        $out = $this->$fn($op, $left, $right, $shouldEval);
+                    } else {
+                        $out = $this->$fn($left, $right, $shouldEval);
+                    }
+
+                    if (isset($out)) {
+                        if ($unitChange && $out[0] === 'number') {
+                            $out = $this->coerceUnit($out, $targetUnit);
+                        }
+
+                        return $out;
+                    }
+                }
+
+                return $this->expToString($value);
+
+            case 'unary':
+                list(, $op, $exp, $inParens) = $value;
+
+                $inExp = $inExp || $this->shouldEval($exp);
+                $exp = $this->reduce($exp);
+
+                if ($exp[0] === 'number') {
+                    switch ($op) {
+                        case '+':
+                            return $exp;
+
+                        case '-':
+                            $exp[1] *= -1;
+
+                            return $exp;
+                    }
+                }
+
+                if ($op === 'not') {
+                    if ($inExp || $inParens) {
+                        if ($exp === self::$false) {
+                            return self::$true;
+                        }
+
+                        return self::$false;
+                    }
+
+                    $op = $op . ' ';
+                }
+
+                return array('string', '', array($op, $exp));
+
+            case 'var':
+                list(, $name) = $value;
+
+                return $this->reduce($this->get($name));
+
+            case 'list':
+                foreach ($value[2] as &$item) {
+                    $item = $this->reduce($item);
+                }
+
+                return $value;
+
+            case 'map':
+                foreach ($value[1] as &$item) {
+                    $item = $this->reduce($item);
+                }
+
+                foreach ($value[2] as &$item) {
+                    $item = $this->reduce($item);
+                }
+
+                return $value;
+
+            case 'string':
+                foreach ($value[2] as &$item) {
+                    if (is_array($item)) {
+                        $item = $this->reduce($item);
+                    }
+                }
+
+                return $value;
+
+            case 'interpolate':
+                $value[1] = $this->reduce($value[1]);
+
+                return $value;
+
+            case 'fncall':
+                list(, $name, $argValues) = $value;
+
+                // user defined function?
+                $func = $this->get(self::$namespaces['function'] . $name, false);
+
+                if ($func) {
+                    $this->pushEnv();
+
+                    // set the args
+                    if (isset($func->args)) {
+                        $this->applyArguments($func->args, $argValues);
+                    }
+
+                    // throw away lines and children
+                    $tmp = (object)array(
+                        'lines' => array(),
+                        'children' => array()
+                    );
+
+                    $ret = $this->compileChildren($func->children, $tmp);
+
+                    $this->popEnv();
+
+                    return ! isset($ret) ? self::$defaultValue : $ret;
+                }
+
+                // built in function
+                if ($this->callBuiltin($name, $argValues, $returnValue)) {
+                    return $returnValue;
+                }
+
+                // need to flatten the arguments into a list
+                $listArgs = array();
+
+                foreach ((array)$argValues as $arg) {
+                    if (empty($arg[0])) {
+                        $listArgs[] = $this->reduce($arg[1]);
+                    }
+                }
+
+                return array('function', $name, array('list', ',', $listArgs));
+
+            default:
+                return $value;
+        }
+    }
+
+    /**
+     * Normalize name
+     *
+     * @param string $name
+     *
+     * @return string
+     */
+    protected function normalizeName($name)
+    {
+        return str_replace('-', '_', $name);
+    }
+
+    /**
+     * Normalize value
+     *
+     * @param array $value
+     *
+     * @return array
+     */
+    public function normalizeValue($value)
+    {
+        $value = $this->coerceForExpression($this->reduce($value));
+        list($type) = $value;
+
+        switch ($type) {
+            case 'list':
+                $value = $this->extractInterpolation($value);
+
+                if ($value[0] !== 'list') {
+                    return array('keyword', $this->compileValue($value));
+                }
+
+                foreach ($value[2] as $key => $item) {
+                    $value[2][$key] = $this->normalizeValue($item);
+                }
+
+                return $value;
+
+            case 'string':
+                return array($type, '"', $this->compileStringContent($value));
+
+            case 'number':
+                return $this->normalizeNumber($value);
+
+            default:
+                return $value;
+        }
+    }
+
+    /**
+     * Normalize number; just does physical lengths for now
+     *
+     * @param array $number
+     *
+     * @return array
+     */
+    protected function normalizeNumber($number)
+    {
+        list(, $value, $unit) = $number;
+
+        if (isset(self::$unitTable['in'][$unit])) {
+            $conv = self::$unitTable['in'][$unit];
+
+            return array('number', $value / $conv, 'in');
+        }
+
+        return $number;
+    }
+
+    /**
+     * Add numbers
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opAddNumberNumber($left, $right)
+    {
+        return array('number', $left[1] + $right[1], $left[2]);
+    }
+
+    /**
+     * Multiply numbers
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opMulNumberNumber($left, $right)
+    {
+        return array('number', $left[1] * $right[1], $left[2]);
+    }
+
+    /**
+     * Subtract numbers
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opSubNumberNumber($left, $right)
+    {
+        return array('number', $left[1] - $right[1], $left[2]);
+    }
+
+    /**
+     * Divide numbers
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opDivNumberNumber($left, $right)
+    {
+        if ($right[1] == 0) {
+            $this->throwError('Division by zero');
+        }
+
+        return array('number', $left[1] / $right[1], $left[2]);
+    }
+
+    /**
+     * Mod numbers
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opModNumberNumber($left, $right)
+    {
+        return array('number', $left[1] % $right[1], $left[2]);
+    }
+
+    /**
+     * Add strings
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opAdd($left, $right)
+    {
+        if ($strLeft = $this->coerceString($left)) {
+            if ($right[0] === 'string') {
+                $right[1] = '';
+            }
+
+            $strLeft[2][] = $right;
+
+            return $strLeft;
+        }
+
+        if ($strRight = $this->coerceString($right)) {
+            if ($left[0] === 'string') {
+                $left[1] = '';
+            }
+
+            array_unshift($strRight[2], $left);
+
+            return $strRight;
+        }
+    }
+
+    /**
+     * Boolean and
+     *
+     * @param array   $left
+     * @param array   $right
+     * @param boolean $shouldEval
+     *
+     * @return array
+     */
+    protected function opAnd($left, $right, $shouldEval)
+    {
+        if (! $shouldEval) {
+            return;
+        }
+
+        if ($left !== self::$false) {
+            return $right;
+        }
+
+        return $left;
+    }
+
+    /**
+     * Boolean or
+     *
+     * @param array   $left
+     * @param array   $right
+     * @param boolean $shouldEval
+     *
+     * @return array
+     */
+    protected function opOr($left, $right, $shouldEval)
+    {
+        if (! $shouldEval) {
+            return;
+        }
+
+        if ($left !== self::$false) {
+            return $left;
+        }
+
+        return $right;
+    }
+
+    /**
+     * Compare colors
+     *
+     * @param string $op
+     * @param array  $left
+     * @param array  $right
+     *
+     * @return array
+     */
+    protected function opColorColor($op, $left, $right)
+    {
+        $out = array('color');
+
+        foreach (range(1, 3) as $i) {
+            $lval = isset($left[$i]) ? $left[$i] : 0;
+            $rval = isset($right[$i]) ? $right[$i] : 0;
+
+            switch ($op) {
+                case '+':
+                    $out[] = $lval + $rval;
+                    break;
+
+                case '-':
+                    $out[] = $lval - $rval;
+                    break;
+
+                case '*':
+                    $out[] = $lval * $rval;
+                    break;
+
+                case '%':
+                    $out[] = $lval % $rval;
+                    break;
+
+                case '/':
+                    if ($rval == 0) {
+                        $this->throwError("color: Can't divide by zero");
+                    }
+
+                    $out[] = (int) ($lval / $rval);
+                    break;
+
+                case '==':
+                    return $this->opEq($left, $right);
+
+                case '!=':
+                    return $this->opNeq($left, $right);
+
+                default:
+                    $this->throwError("color: unknown op $op");
+            }
+        }
+
+        if (isset($left[4])) {
+            $out[4] = $left[4];
+        } elseif (isset($right[4])) {
+            $out[4] = $right[4];
+        }
+
+        return $this->fixColor($out);
+    }
+
+    /**
+     * Compare color and number
+     *
+     * @param string $op
+     * @param array  $left
+     * @param array  $right
+     *
+     * @return array
+     */
+    protected function opColorNumber($op, $left, $right)
+    {
+        $value = $right[1];
+
+        return $this->opColorColor(
+            $op,
+            $left,
+            array('color', $value, $value, $value)
+        );
+    }
+
+    /**
+     * Compare number and color
+     *
+     * @param string $op
+     * @param array  $left
+     * @param array  $right
+     *
+     * @return array
+     */
+    protected function opNumberColor($op, $left, $right)
+    {
+        $value = $left[1];
+
+        return $this->opColorColor(
+            $op,
+            array('color', $value, $value, $value),
+            $right
+        );
+    }
+
+    /**
+     * Compare number1 == number2
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opEq($left, $right)
+    {
+        if (($lStr = $this->coerceString($left)) && ($rStr = $this->coerceString($right))) {
+            $lStr[1] = '';
+            $rStr[1] = '';
+
+            $left = $this->compileValue($lStr);
+            $right = $this->compileValue($rStr);
+        }
+
+        return $this->toBool($left === $right);
+    }
+
+    /**
+     * Compare number1 != number2
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opNeq($left, $right)
+    {
+        if (($lStr = $this->coerceString($left)) && ($rStr = $this->coerceString($right))) {
+            $lStr[1] = '';
+            $rStr[1] = '';
+
+            $left = $this->compileValue($lStr);
+            $right = $this->compileValue($rStr);
+        }
+
+        return $this->toBool($left !== $right);
+    }
+
+    /**
+     * Compare number1 >= number2
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opGteNumberNumber($left, $right)
+    {
+        return $this->toBool($left[1] >= $right[1]);
+    }
+
+    /**
+     * Compare number1 > number2
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opGtNumberNumber($left, $right)
+    {
+        return $this->toBool($left[1] > $right[1]);
+    }
+
+    /**
+     * Compare number1 <= number2
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opLteNumberNumber($left, $right)
+    {
+        return $this->toBool($left[1] <= $right[1]);
+    }
+
+    /**
+     * Compare number1 < number2
+     *
+     * @param array $left
+     * @param array $right
+     *
+     * @return array
+     */
+    protected function opLtNumberNumber($left, $right)
+    {
+        return $this->toBool($left[1] < $right[1]);
+    }
+
+    /**
+     * Cast to boolean
+     *
+     * @api
+     *
+     * @param mixed $thing
+     *
+     * @return array
+     */
+    public function toBool($thing)
+    {
+        return $thing ? self::$true : self::$false;
+    }
+
+    /**
+     * Compiles a primitive value into a CSS property value.
+     *
+     * Values in scssphp are typed by being wrapped in arrays, their format is
+     * typically:
+     *
+     *     array(type, contents [, additional_contents]*)
+     *
+     * The input is expected to be reduced. This function will not work on
+     * things like expressions and variables.
+     *
+     * @api
+     *
+     * @param array $value
+     *
+     * @return string
+     */
+    public function compileValue($value)
+    {
+        $value = $this->reduce($value);
+
+        list($type) = $value;
+
+        switch ($type) {
+            case 'keyword':
+                return $value[1];
+
+            case 'color':
+                // [1] - red component (either number for a %)
+                // [2] - green component
+                // [3] - blue component
+                // [4] - optional alpha component
+                list(, $r, $g, $b) = $value;
+
+                $r = round($r);
+                $g = round($g);
+                $b = round($b);
+
+                if (count($value) === 5 && $value[4] !== 1) { // rgba
+                    return 'rgba(' . $r . ', ' . $g . ', ' . $b . ', ' . $value[4] . ')';
+                }
+
+                $h = sprintf('#%02x%02x%02x', $r, $g, $b);
+
+                // Converting hex color to short notation (e.g. #003399 to #039)
+                if ($h[1] === $h[2] && $h[3] === $h[4] && $h[5] === $h[6]) {
+                    $h = '#' . $h[1] . $h[3] . $h[5];
+                }
+
+                return $h;
+
+            case 'number':
+                return round($value[1], $this->numberPrecision) . $value[2];
+
+            case 'string':
+                return $value[1] . $this->compileStringContent($value) . $value[1];
+
+            case 'function':
+                $args = ! empty($value[2]) ? $this->compileValue($value[2]) : '';
+
+                return "$value[1]($args)";
+
+            case 'list':
+                $value = $this->extractInterpolation($value);
+
+                if ($value[0] !== 'list') {
+                    return $this->compileValue($value);
+                }
+
+                list(, $delim, $items) = $value;
+
+                $filtered = array();
+
+                foreach ($items as $item) {
+                    if ($item[0] === 'null') {
+                        continue;
+                    }
+
+                    $filtered[] = $this->compileValue($item);
+                }
+
+                return implode("$delim ", $filtered);
+
+            case 'map':
+                $keys = $value[1];
+                $values = $value[2];
+                $filtered = array();
+
+                for ($i = 0, $s = count($keys); $i < $s; $i++) {
+                    $filtered[$this->compileValue($keys[$i])] = $this->compileValue($values[$i]);
+                }
+
+                array_walk($filtered, function (&$value, $key) {
+                    $value = $key . ': ' . $value;
+                });
+
+                return '(' . implode(', ', $filtered) . ')';
+
+            case 'interpolated':
+                // node created by extractInterpolation
+                list(, $interpolate, $left, $right) = $value;
+                list(,, $whiteLeft, $whiteRight) = $interpolate;
+
+                $left = count($left[2]) > 0 ?
+                    $this->compileValue($left) . $whiteLeft : '';
+
+                $right = count($right[2]) > 0 ?
+                    $whiteRight . $this->compileValue($right) : '';
+
+                return $left . $this->compileValue($interpolate) . $right;
+
+            case 'interpolate':
+                // raw parse node
+                list(, $exp) = $value;
+
+                // strip quotes if it's a string
+                $reduced = $this->reduce($exp);
+                switch ($reduced[0]) {
+                    case 'string':
+                        $reduced = array('keyword', $this->compileStringContent($reduced));
+                        break;
+
+                    case 'null':
+                        $reduced = array('keyword', '');
+                }
+
+                return $this->compileValue($reduced);
+
+            case 'null':
+                return 'null';
+
+            default:
+                $this->throwError("unknown value type: $type");
+        }
+    }
+
+    /**
+     * Flatten list
+     *
+     * @param array $list
+     *
+     * @return string
+     */
+    protected function flattenList($list)
+    {
+        return $this->compileValue($list);
+    }
+
+    /**
+     * Compile string content
+     *
+     * @param array $string
+     *
+     * @return string
+     */
+    protected function compileStringContent($string)
+    {
+        $parts = array();
+
+        foreach ($string[2] as $part) {
+            if (is_array($part)) {
+                $parts[] = $this->compileValue($part);
+            } else {
+                $parts[] = $part;
+            }
+        }
+
+        return implode($parts);
+    }
+
+    /**
+     * Extract interpolation; it doesn't need to be recursive, compileValue will handle that
+     *
+     * @param array $list
+     *
+     * @return array
+     */
+    protected function extractInterpolation($list)
+    {
+        $items = $list[2];
+
+        foreach ($items as $i => $item) {
+            if ($item[0] === 'interpolate') {
+                $before = array('list', $list[1], array_slice($items, 0, $i));
+                $after = array('list', $list[1], array_slice($items, $i + 1));
+
+                return array('interpolated', $item, $before, $after);
+            }
+        }
+
+        return $list;
+    }
+
+    /**
+     * Find the final set of selectors
+     *
+     * @param \stdClass $env
+     *
+     * @return array
+     */
+    protected function multiplySelectors($env)
+    {
+        $envs = array();
+
+        while (null !== $env) {
+            if (! empty($env->selectors)) {
+                $envs[] = $env;
+            }
+
+            $env = $env->parent;
+        };
+
+        $selectors = array();
+        $parentSelectors = array(array());
+
+        while ($env = array_pop($envs)) {
+            $selectors = array();
+
+            foreach ($env->selectors as $selector) {
+                foreach ($parentSelectors as $parent) {
+                    $selectors[] = $this->joinSelectors($parent, $selector);
+                }
+            }
+
+            $parentSelectors = $selectors;
+        }
+
+        return $selectors;
+    }
+
+    /**
+     * Join selectors; looks for & to replace, or append parent before child
+     *
+     * @param array $parent
+     * @param array $child
+     *
+     * @return array
+     */
+    protected function joinSelectors($parent, $child)
+    {
+        $setSelf = false;
+        $out = array();
+
+        foreach ($child as $part) {
+            $newPart = array();
+
+            foreach ($part as $p) {
+                if ($p === self::$selfSelector) {
+                    $setSelf = true;
+
+                    foreach ($parent as $i => $parentPart) {
+                        if ($i > 0) {
+                            $out[] = $newPart;
+                            $newPart = array();
+                        }
+
+                        foreach ($parentPart as $pp) {
+                            $newPart[] = $pp;
+                        }
+                    }
+                } else {
+                    $newPart[] = $p;
+                }
+            }
+
+            $out[] = $newPart;
+        }
+
+        return $setSelf ? $out : array_merge($parent, $child);
+    }
+
+    /**
+     * Multiply media
+     *
+     * @param \stdClass $env
+     * @param array     $childQueries
+     *
+     * @return array
+     */
+    protected function multiplyMedia($env, $childQueries = null)
+    {
+        if (! isset($env) ||
+            ! empty($env->block->type) && $env->block->type !== 'media'
+        ) {
+            return $childQueries;
+        }
+
+        // plain old block, skip
+        if (empty($env->block->type)) {
+            return $this->multiplyMedia($env->parent, $childQueries);
+        }
+
+        $parentQueries = $env->block->queryList;
+        if ($childQueries === null) {
+            $childQueries = $parentQueries;
+        } else {
+            $originalQueries = $childQueries;
+            $childQueries = array();
+
+            foreach ($parentQueries as $parentQuery) {
+                foreach ($originalQueries as $childQuery) {
+                    $childQueries []= array_merge($parentQuery, $childQuery);
+                }
+            }
+        }
+
+        return $this->multiplyMedia($env->parent, $childQueries);
+    }
+
+    /**
+     * Push environment
+     *
+     * @param \stdClass $block
+     *
+     * @return \stdClass
+     */
+    protected function pushEnv($block = null)
+    {
+        $env = new \stdClass;
+        $env->parent = $this->env;
+        $env->store = array();
+        $env->block = $block;
+        $env->depth = isset($this->env->depth) ? $this->env->depth + 1 : 0;
+
+        $this->env = $env;
+
+        return $env;
+    }
+
+    /**
+     * Pop environment
+     */
+    protected function popEnv()
+    {
+        $env = $this->env;
+        $this->env = $this->env->parent;
+
+        return $env;
+    }
+
+    /**
+     * Get store environment
+     *
+     * @return \stdClass
+     */
+    protected function getStoreEnv()
+    {
+        return isset($this->storeEnv) ? $this->storeEnv : $this->env;
+    }
+
+    /**
+     * Set variable
+     *
+     * @param string    $name
+     * @param mixed     $value
+     * @param boolean   $shadow
+     * @param \stdClass $env
+     */
+    protected function set($name, $value, $shadow = false, $env = null)
+    {
+        $name = $this->normalizeName($name);
+
+        if ($shadow) {
+            $this->setRaw($name, $value, $env);
+        } else {
+            $this->setExisting($name, $value, $env);
+        }
+    }
+
+    /**
+     * Set existing variable
+     *
+     * @param string    $name
+     * @param mixed     $value
+     * @param \stdClass $env
+     */
+    protected function setExisting($name, $value, $env = null)
+    {
+        if (! isset($env)) {
+            $env = $this->getStoreEnv();
+        }
+
+        $storeEnv = $env;
+
+        $hasNamespace = $name[0] === '^' || $name[0] === '@' || $name[0] === '%';
+
+        for (;;) {
+            if (array_key_exists($name, $env->store)) {
+                break;
+            }
+
+            if (! $hasNamespace && isset($env->marker)) {
+                $env = $storeEnv;
+                break;
+            }
+
+            if (! isset($env->parent)) {
+                $env = $storeEnv;
+                break;
+            }
+
+            $env = $env->parent;
+        }
+
+        $env->store[$name] = $value;
+    }
+
+    /**
+     * Set raw variable
+     *
+     * @param string    $name
+     * @param mixed     $value
+     * @param \stdClass $env
+     */
+    protected function setRaw($name, $value, $env = null)
+    {
+        if (! isset($env)) {
+            $env = $this->getStoreEnv();
+        }
+
+        $env->store[$name] = $value;
+    }
+
+    /**
+     * Get variable
+     *
+     * @api
+     *
+     * @param string    $name
+     * @param boolean   $shouldThrow
+     * @param \stdClass $env
+     *
+     * @return mixed
+     */
+    public function get($name, $shouldThrow = true, $env = null)
+    {
+        $name = $this->normalizeName($name);
+
+        if (! isset($env)) {
+            $env = $this->getStoreEnv();
+        }
+
+        $hasNamespace = $name[0] === '^' || $name[0] === '@' || $name[0] === '%';
+
+        for (;;) {
+            if (array_key_exists($name, $env->store)) {
+                return $env->store[$name];
+            }
+
+            if (! $hasNamespace && isset($env->marker)) {
+                $env = $this->rootEnv;
+                continue;
+            }
+
+            if (! isset($env->parent)) {
+                break;
+            }
+
+            $env = $env->parent;
+        }
+
+        if ($shouldThrow) {
+            $this->throwError("Undefined variable \$$name");
+        }
+
+        // found nothing
+    }
+
+    /**
+     * Has variable?
+     *
+     * @param string    $name
+     * @param \stdClass $env
+     *
+     * @return boolean
+     */
+    protected function has($name, $env = null)
+    {
+        return $this->get($name, false, $env) !== null;
+    }
+
+    /**
+     * Inject variables
+     *
+     * @param array $args
+     */
+    protected function injectVariables(array $args)
+    {
+        if (empty($args)) {
+            return;
+        }
+
+        $parser = new Parser(__METHOD__, false);
+
+        foreach ($args as $name => $strValue) {
+            if ($name[0] === '$') {
+                $name = substr($name, 1);
+            }
+
+            if (! $parser->parseValue($strValue, $value)) {
+                $value = $this->coerceValue($strValue);
+            }
+
+            $this->set($name, $value);
+        }
+    }
+
+    /**
+     * Set variables
+     *
+     * @api
+     *
+     * @param array $variables
+     */
+    public function setVariables(array $variables)
+    {
+        $this->registeredVars = array_merge($this->registeredVars, $variables);
+    }
+
+    /**
+     * Unset variable
+     *
+     * @api
+     *
+     * @param string $name
+     */
+    public function unsetVariable($name)
+    {
+        unset($this->registeredVars[$name]);
+    }
+
+    /**
+     * Returns list of parsed files
+     *
+     * @api
+     *
+     * @return array
+     */
+    public function getParsedFiles()
+    {
+        return $this->parsedFiles;
+    }
+
+    /**
+     * Add import path
+     *
+     * @api
+     *
+     * @param string $path
+     */
+    public function addImportPath($path)
+    {
+        if (! in_array($path, $this->importPaths)) {
+            $this->importPaths[] = $path;
+        }
+    }
+
+    /**
+     * Set import paths
+     *
+     * @api
+     *
+     * @param string|array $path
+     */
+    public function setImportPaths($path)
+    {
+        $this->importPaths = (array)$path;
+    }
+
+    /**
+     * Set number precision
+     *
+     * @api
+     *
+     * @param integer $numberPrecision
+     */
+    public function setNumberPrecision($numberPrecision)
+    {
+        $this->numberPrecision = $numberPrecision;
+    }
+
+    /**
+     * Set formatter
+     *
+     * @api
+     *
+     * @param string $formatterName
+     */
+    public function setFormatter($formatterName)
+    {
+        $this->formatter = $formatterName;
+    }
+
+    /**
+     * Set line number style
+     *
+     * @api
+     *
+     * @param string $lineNumberStyle
+     */
+    public function setLineNumberStyle($lineNumberStyle)
+    {
+        $this->lineNumberStyle = $lineNumberStyle;
+    }
+
+    /**
+     * Register function
+     *
+     * @api
+     *
+     * @param string   $name
+     * @param callable $func
+     */
+    public function registerFunction($name, $func)
+    {
+        $this->userFunctions[$this->normalizeName($name)] = $func;
+    }
+
+    /**
+     * Unregister function
+     *
+     * @api
+     *
+     * @param string $name
+     */
+    public function unregisterFunction($name)
+    {
+        unset($this->userFunctions[$this->normalizeName($name)]);
+    }
+
+    /**
+     * Import file
+     *
+     * @param string $path
+     * @param array  $out
+     */
+    protected function importFile($path, $out)
+    {
+        // see if tree is cached
+        $realPath = realpath($path);
+
+        if (isset($this->importCache[$realPath])) {
+            $this->handleImportLoop($realPath);
+
+            $tree = $this->importCache[$realPath];
+        } else {
+            $code = file_get_contents($path);
+            $parser = new Parser($path, false);
+            $tree = $parser->parse($code);
+
+            $this->parsedFiles[$realPath] = filemtime($path);
+            $this->importCache[$realPath] = $tree;
+        }
+
+        $pi = pathinfo($path);
+        array_unshift($this->importPaths, $pi['dirname']);
+        $this->compileChildren($tree->children, $out);
+        array_shift($this->importPaths);
+    }
+
+    /**
+     * Return the file path for an import url if it exists
+     *
+     * @api
+     *
+     * @param string $url
+     *
+     * @return string|null
+     */
+    public function findImport($url)
+    {
+        $urls = array();
+
+        // for "normal" scss imports (ignore vanilla css and external requests)
+        if (! preg_match('/\.css$|^https?:\/\//', $url)) {
+            // try both normal and the _partial filename
+            $urls = array($url, preg_replace('/[^\/]+$/', '_\0', $url));
+        }
+
+        foreach ($this->importPaths as $dir) {
+            if (is_string($dir)) {
+                // check urls for normal import paths
+                foreach ($urls as $full) {
+                    $full = $dir .
+                        (! empty($dir) && substr($dir, -1) !== '/' ? '/' : '') .
+                        $full;
+
+                    if ($this->fileExists($file = $full . '.scss') ||
+                        $this->fileExists($file = $full)
+                    ) {
+                        return $file;
+                    }
+                }
+            } elseif (is_callable($dir)) {
+                // check custom callback for import path
+                $file = call_user_func($dir, $url, $this);
+
+                if ($file !== null) {
+                    return $file;
+                }
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Throw error (exception)
+     *
+     * @api
+     *
+     * @param string $msg Message with optional sprintf()-style vararg parameters
+     *
+     * @throws \Exception
+     */
+    public function throwError($msg)
+    {
+        if (func_num_args() > 1) {
+            $msg = call_user_func_array('sprintf', func_get_args());
+        }
+
+        if ($this->sourcePos >= 0 && isset($this->sourceParser)) {
+            $this->sourceParser->throwParseError($msg, $this->sourcePos);
+        }
+
+        throw new \Exception($msg);
+    }
+
+    /**
+     * Handle import loop
+     *
+     * @param string $name
+     *
+     * @throws \Exception
+     */
+    private function handleImportLoop($name)
+    {
+        for ($env = $this->env; $env; $env = $env->parent) {
+            $file = $env->block->sourceParser->getSourceName();
+
+            if (realpath($file) === $name) {
+                $this->throwError(
+                    'An @import loop has been found: %s imports %s',
+                    $this->env->block->sourceParser->getSourceName(),
+                    basename($file)
+                );
+            }
+        }
+    }
+
+    /**
+     * Does file exist?
+     *
+     * @param string $name
+     *
+     * @return boolean
+     */
+    protected function fileExists($name)
+    {
+        return is_file($name);
+    }
+
+    /**
+     * Call built-in and registered (PHP) functions
+     *
+     * @param string $name
+     * @param array  $args
+     * @param array  $returnValue
+     *
+     * @return boolean Returns true if returnValue is set; otherwise, false
+     */
+    protected function callBuiltin($name, $args, &$returnValue)
+    {
+        // try a lib function
+        $name = $this->normalizeName($name);
+
+        if (isset($this->userFunctions[$name])) {
+            // see if we can find a user function
+            $fn = $this->userFunctions[$name];
+
+            foreach ($args as &$val) {
+                $val = $this->reduce($val[1], true);
+            }
+
+            $returnValue = call_user_func($fn, $args, $this);
+        } else {
+            $f = $this->getBuiltinFunction($name);
+
+            if (is_callable($f)) {
+                $libName = $f[1];
+
+                $prototype = isset(self::$$libName) ? self::$$libName : null;
+                $sorted = $this->sortArgs($prototype, $args);
+
+                foreach ($sorted as &$val) {
+                    $val = $this->reduce($val, true);
+                }
+
+                $returnValue = call_user_func($f, $sorted, $this);
+            }
+        }
+
+        if (isset($returnValue)) {
+            $returnValue = $this->coerceValue($returnValue);
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Get built-in function
+     *
+     * @param string $name Normalized name
+     *
+     * @return array
+     */
+    protected function getBuiltinFunction($name)
+    {
+        $libName = 'lib' . preg_replace_callback(
+            '/_(.)/',
+            function ($m) {
+                return ucfirst($m[1]);
+            },
+            ucfirst($name)
+        );
+
+        return array($this, $libName);
+    }
+
+    /**
+     * Sorts keyword arguments
+     *
+     * @todo Merge with applyArguments()?
+     *
+     * @param array $prototype
+     * @param array $args
+     *
+     * @return array
+     */
+    protected function sortArgs($prototype, $args)
+    {
+        $keyArgs = array();
+        $posArgs = array();
+
+        foreach ($args as $arg) {
+            list($key, $value) = $arg;
+
+            $key = $key[1];
+
+            if (empty($key)) {
+                $posArgs[] = $value;
+            } else {
+                $keyArgs[$key] = $value;
+            }
+        }
+
+        if (! isset($prototype)) {
+            return $posArgs;
+        }
+
+        $finalArgs = array();
+
+        foreach ($prototype as $i => $names) {
+            if (isset($posArgs[$i])) {
+                $finalArgs[] = $posArgs[$i];
+                continue;
+            }
+
+            $set = false;
+
+            foreach ((array)$names as $name) {
+                if (isset($keyArgs[$name])) {
+                    $finalArgs[] = $keyArgs[$name];
+                    $set = true;
+                    break;
+                }
+            }
+
+            if (! $set) {
+                $finalArgs[] = null;
+            }
+        }
+
+        return $finalArgs;
+    }
+
+    /**
+     * Apply argument values per definition
+     *
+     * @param array $argDef
+     * @param array $argValues
+     *
+     * @throws \Exception
+     */
+    protected function applyArguments($argDef, $argValues)
+    {
+        $storeEnv = $this->getStoreEnv();
+
+        $env = new \stdClass;
+        $env->store = $storeEnv->store;
+
+        $hasVariable = false;
+        $args = array();
+
+        foreach ($argDef as $i => $arg) {
+            list($name, $default, $isVariable) = $argDef[$i];
+
+            $args[$name] = array($i, $name, $default, $isVariable);
+            $hasVariable |= $isVariable;
+        }
+
+        $keywordArgs = array();
+        $deferredKeywordArgs = array();
+        $remaining = array();
+
+        // assign the keyword args
+        foreach ((array) $argValues as $arg) {
+            if (! empty($arg[0])) {
+                if (! isset($args[$arg[0][1]])) {
+                    if ($hasVariable) {
+                        $deferredKeywordArgs[$arg[0][1]] = $arg[1];
+                    } else {
+                        $this->throwError("Mixin or function doesn't have an argument named $%s.", $arg[0][1]);
+                    }
+                } elseif ($args[$arg[0][1]][0] < count($remaining)) {
+                    $this->throwError("The argument $%s was passed both by position and by name.", $arg[0][1]);
+                } else {
+                    $keywordArgs[$arg[0][1]] = $arg[1];
+                }
+            } elseif (count($keywordArgs)) {
+                $this->throwError('Positional arguments must come before keyword arguments.');
+            } elseif ($arg[2] === true) {
+                $val = $this->reduce($arg[1], true);
+
+                if ($val[0] === 'list') {
+                    foreach ($val[2] as $name => $item) {
+                        if (! is_numeric($name)) {
+                            $keywordArgs[$name] = $item;
+                        } else {
+                            $remaining[] = $item;
+                        }
+                    }
+                } else {
+                    $remaining[] = $val;
+                }
+            } else {
+                $remaining[] = $arg[1];
+            }
+        }
+
+        foreach ($args as $arg) {
+            list($i, $name, $default, $isVariable) = $arg;
+
+            if ($isVariable) {
+                $val = array('list', ',', array(), $isVariable);
+
+                for ($count = count($remaining); $i < $count; $i++) {
+                    $val[2][] = $remaining[$i];
+                }
+
+                foreach ($deferredKeywordArgs as $itemName => $item) {
+                    $val[2][$itemName] = $item;
+                }
+            } elseif (isset($remaining[$i])) {
+                $val = $remaining[$i];
+            } elseif (isset($keywordArgs[$name])) {
+                $val = $keywordArgs[$name];
+            } elseif (! empty($default)) {
+                continue;
+            } else {
+                $this->throwError("Missing argument $name");
+            }
+
+            $this->set($name, $this->reduce($val, true), true, $env);
+        }
+
+        $storeEnv->store = $env->store;
+
+        foreach ($args as $arg) {
+            list($i, $name, $default, $isVariable) = $arg;
+
+            if ($isVariable || isset($remaining[$i]) || isset($keywordArgs[$name]) || empty($default)) {
+                continue;
+            }
+
+            $this->set($name, $this->reduce($default, true), true);
+        }
+    }
+
+    /**
+     * Coerce a php value into a scss one
+     *
+     * @param mixed $value
+     *
+     * @return array
+     */
+    private function coerceValue($value)
+    {
+        if (is_array($value)) {
+            return $value;
+        }
+
+        if (is_bool($value)) {
+            return $value ? self::$true : self::$false;
+        }
+
+        if ($value === null) {
+            $value = self::$null;
+        }
+
+        if (is_numeric($value)) {
+            return array('number', $value, '');
+        }
+
+        if ($value === '') {
+            return self::$emptyString;
+        }
+
+        return array('keyword', $value);
+    }
+
+    /**
+     * Coerce unit on number to be normalized
+     *
+     * @param array  $number
+     * @param string $unit
+     *
+     * @return array
+     */
+    protected function coerceUnit($number, $unit)
+    {
+        list(, $value, $baseUnit) = $number;
+
+        if (isset(self::$unitTable[$baseUnit][$unit])) {
+            $value = $value * self::$unitTable[$baseUnit][$unit];
+        }
+
+        return array('number', $value, $unit);
+    }
+
+    /**
+     * Coerce something to map
+     *
+     * @param array $item
+     *
+     * @return array
+     */
+    protected function coerceMap($item)
+    {
+        if ($item[0] === 'map') {
+            return $item;
+        }
+
+        if ($item === self::$emptyList) {
+            return self::$emptyMap;
+        }
+
+        return array('map', array($item), array(self::$null));
+    }
+
+    /**
+     * Coerce something to list
+     *
+     * @param array $item
+     *
+     * @return array
+     */
+    protected function coerceList($item, $delim = ',')
+    {
+        if (isset($item) && $item[0] === 'list') {
+            return $item;
+        }
+
+        if (isset($item) && $item[0] === 'map') {
+            $keys = $item[1];
+            $values = $item[2];
+            $list = array();
+
+            for ($i = 0, $s = count($keys); $i < $s; $i++) {
+                $key = $keys[$i];
+                $value = $values[$i];
+
+                $list[] = array('list', '', array(array('keyword', $this->compileValue($key)), $value));
+            }
+
+            return array('list', ',', $list);
+        }
+
+        return array('list', $delim, ! isset($item) ? array(): array($item));
+    }
+
+    /**
+     * Coerce color for expression
+     *
+     * @param array $value
+     *
+     * @return array|null
+     */
+    protected function coerceForExpression($value)
+    {
+        if ($color = $this->coerceColor($value)) {
+            return $color;
+        }
+
+        return $value;
+    }
+
+    /**
+     * Coerce value to color
+     *
+     * @param array $value
+     *
+     * @return array|null
+     */
+    protected function coerceColor($value)
+    {
+        switch ($value[0]) {
+            case 'color':
+                return $value;
+
+            case 'keyword':
+                $name = strtolower($value[1]);
+
+                if (isset(Colors::$cssColors[$name])) {
+                    $rgba = explode(',', Colors::$cssColors[$name]);
+
+                    return isset($rgba[3])
+                        ? array('color', (int) $rgba[0], (int) $rgba[1], (int) $rgba[2], (int) $rgba[3])
+                        : array('color', (int) $rgba[0], (int) $rgba[1], (int) $rgba[2]);
+                }
+
+                return null;
+        }
+
+        return null;
+    }
+
+    /**
+     * Coerce value to string
+     *
+     * @param array $value
+     *
+     * @return array|null
+     */
+    protected function coerceString($value)
+    {
+        if ($value[0] === 'string') {
+            return $value;
+        }
+
+        return array('string', '', array($this->compileValue($value)));
+    }
+
+    /**
+     * Coerce value to a percentage
+     *
+     * @param array $value
+     *
+     * @return integer|float
+     */
+    protected function coercePercent($value)
+    {
+        if ($value[0] === 'number') {
+            if ($value[2] === '%') {
+                return $value[1] / 100;
+            }
+
+            return $value[1];
+        }
+
+        return 0;
+    }
+
+    /**
+     * Assert value is a map
+     *
+     * @api
+     *
+     * @param array $value
+     *
+     * @return array
+     *
+     * @throws \Exception
+     */
+    public function assertMap($value)
+    {
+        $value = $this->coerceMap($value);
+
+        if ($value[0] !== 'map') {
+            $this->throwError('expecting map');
+        }
+
+        return $value;
+    }
+
+    /**
+     * Assert value is a list
+     *
+     * @api
+     *
+     * @param array $value
+     *
+     * @return array
+     *
+     * @throws \Exception
+     */
+    public function assertList($value)
+    {
+        if ($value[0] !== 'list') {
+            $this->throwError('expecting list');
+        }
+
+        return $value;
+    }
+
+    /**
+     * Assert value is a color
+     *
+     * @api
+     *
+     * @param array $value
+     *
+     * @return array
+     *
+     * @throws \Exception
+     */
+    public function assertColor($value)
+    {
+        if ($color = $this->coerceColor($value)) {
+            return $color;
+        }
+
+        $this->throwError('expecting color');
+    }
+
+    /**
+     * Assert value is a number
+     *
+     * @api
+     *
+     * @param array $value
+     *
+     * @return integer|float
+     *
+     * @throws \Exception
+     */
+    public function assertNumber($value)
+    {
+        if ($value[0] !== 'number') {
+            $this->throwError('expecting number');
+        }
+
+        return $value[1];
+    }
+
+    /**
+     * Make sure a color's components don't go out of bounds
+     *
+     * @param array $c
+     *
+     * @return array
+     */
+    protected function fixColor($c)
+    {
+        foreach (range(1, 3) as $i) {
+            if ($c[$i] < 0) {
+                $c[$i] = 0;
+            }
+
+            if ($c[$i] > 255) {
+                $c[$i] = 255;
+            }
+        }
+
+        return $c;
+    }
+
+    /**
+     * Convert RGB to HSL
+     *
+     * @api
+     *
+     * @param integer $red
+     * @param integer $green
+     * @param integer $blue
+     *
+     * @return array
+     */
+    public function toHSL($red, $green, $blue)
+    {
+        $min = min($red, $green, $blue);
+        $max = max($red, $green, $blue);
+
+        $l = $min + $max;
+        $d = $max - $min;
+
+        if ((int) $d === 0) {
+            $h = $s = 0;
+        } else {
+            if ($l < 255) {
+                $s = $d / $l;
+            } else {
+                $s = $d / (510 - $l);
+            }
+
+            if ($red == $max) {
+                $h = 60 * ($green - $blue) / $d;
+            } elseif ($green == $max) {
+                $h = 60 * ($blue - $red) / $d + 120;
+            } elseif ($blue == $max) {
+                $h = 60 * ($red - $green) / $d + 240;
+            }
+        }
+
+        return array('hsl', fmod($h, 360), $s * 100, $l / 5.1);
+    }
+
+    /**
+     * Hue to RGB helper
+     *
+     * @param float $m1
+     * @param float $m2
+     * @param float $h
+     *
+     * @return float
+     */
+    private function hueToRGB($m1, $m2, $h)
+    {
+        if ($h < 0) {
+            $h += 1;
+        } elseif ($h > 1) {
+            $h -= 1;
+        }
+
+        if ($h * 6 < 1) {
+            return $m1 + ($m2 - $m1) * $h * 6;
+        }
+
+        if ($h * 2 < 1) {
+            return $m2;
+        }
+
+        if ($h * 3 < 2) {
+            return $m1 + ($m2 - $m1) * (2/3 - $h) * 6;
+        }
+
+        return $m1;
+    }
+
+    /**
+     * Convert HSL to RGB
+     *
+     * @api
+     *
+     * @param integer $hue        H from 0 to 360
+     * @param integer $saturation S from 0 to 100
+     * @param integer $lightness  L from 0 to 100
+     *
+     * @return array
+     */
+    public function toRGB($hue, $saturation, $lightness)
+    {
+        if ($hue < 0) {
+            $hue += 360;
+        }
+
+        $h = $hue / 360;
+        $s = min(100, max(0, $saturation)) / 100;
+        $l = min(100, max(0, $lightness)) / 100;
+
+        $m2 = $l <= 0.5 ? $l * ($s + 1) : $l + $s - $l * $s;
+        $m1 = $l * 2 - $m2;
+
+        $r = $this->hueToRGB($m1, $m2, $h + 1/3) * 255;
+        $g = $this->hueToRGB($m1, $m2, $h) * 255;
+        $b = $this->hueToRGB($m1, $m2, $h - 1/3) * 255;
+
+        $out = array('color', $r, $g, $b);
+
+        return $out;
+    }
+
+    // Built in functions
+
+    protected static $libIf = array('condition', 'if-true', 'if-false');
+    protected function libIf($args)
+    {
+        list($cond, $t, $f) = $args;
+
+        if (! $this->isTruthy($cond)) {
+            return $f;
+        }
+
+        return $t;
+    }
+
+    protected static $libIndex = array('list', 'value');
+    protected function libIndex($args)
+    {
+        list($list, $value) = $args;
+
+        if ($value[0] === 'map') {
+            return self::$null;
+        }
+
+        if ($list[0] === 'map') {
+            $list = $this->coerceList($list, ' ');
+        }
+
+        if ($list[0] !== 'list') {
+            return self::$null;
+        }
+
+        $values = array();
+
+        foreach ($list[2] as $item) {
+            $values[] = $this->normalizeValue($item);
+        }
+
+        $key = array_search($this->normalizeValue($value), $values);
+
+        return false === $key ? self::$null : $key + 1;
+    }
+
+    protected static $libRgb = array('red', 'green', 'blue');
+    protected function libRgb($args)
+    {
+        list($r, $g, $b) = $args;
+
+        return array('color', $r[1], $g[1], $b[1]);
+    }
+
+    protected static $libRgba = array(
+        array('red', 'color'),
+        'green', 'blue', 'alpha');
+    protected function libRgba($args)
+    {
+        if ($color = $this->coerceColor($args[0])) {
+            // workaround https://github.com/facebook/hhvm/issues/5457
+            reset($args);
+
+            $num = ! isset($args[1]) ? $args[3] : $args[1];
+            $alpha = $this->assertNumber($num);
+            $color[4] = $alpha;
+
+            return $color;
+        }
+
+        list($r, $g, $b, $a) = $args;
+
+        return array('color', $r[1], $g[1], $b[1], $a[1]);
+    }
+
+    // helper function for adjust_color, change_color, and scale_color
+    protected function alterColor($args, $fn)
+    {
+        $color = $this->assertColor($args[0]);
+
+        // workaround https://github.com/facebook/hhvm/issues/5457
+        reset($args);
+
+        foreach (array(1, 2, 3, 7) as $i) {
+            if (isset($args[$i])) {
+                $val = $this->assertNumber($args[$i]);
+                $ii = $i === 7 ? 4 : $i; // alpha
+                $color[$ii] = call_user_func($fn, isset($color[$ii]) ? $color[$ii] : 0, $val, $i);
+            }
+        }
+
+        if (isset($args[4]) || isset($args[5]) || isset($args[6])) {
+            $hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+            foreach (array(4, 5, 6) as $i) {
+                if (isset($args[$i])) {
+                    $val = $this->assertNumber($args[$i]);
+                    $hsl[$i - 3] = call_user_func($fn, $hsl[$i - 3], $val, $i);
+                }
+            }
+
+            $rgb = $this->toRGB($hsl[1], $hsl[2], $hsl[3]);
+
+            if (isset($color[4])) {
+                $rgb[4] = $color[4];
+            }
+
+            $color = $rgb;
+        }
+
+        return $color;
+    }
+
+    protected static $libAdjustColor = array(
+        'color', 'red', 'green', 'blue',
+        'hue', 'saturation', 'lightness', 'alpha'
+    );
+    protected function libAdjustColor($args)
+    {
+        return $this->alterColor($args, function ($base, $alter, $i) {
+            return $base + $alter;
+        });
+    }
+
+    protected static $libChangeColor = array(
+        'color', 'red', 'green', 'blue',
+        'hue', 'saturation', 'lightness', 'alpha'
+    );
+    protected function libChangeColor($args)
+    {
+        return $this->alterColor($args, function ($base, $alter, $i) {
+            return $alter;
+        });
+    }
+
+    protected static $libScaleColor = array(
+        'color', 'red', 'green', 'blue',
+        'hue', 'saturation', 'lightness', 'alpha'
+    );
+    protected function libScaleColor($args)
+    {
+        return $this->alterColor($args, function ($base, $scale, $i) {
+            // 1, 2, 3 - rgb
+            // 4, 5, 6 - hsl
+            // 7 - a
+            switch ($i) {
+                case 1:
+                case 2:
+                case 3:
+                    $max = 255;
+                    break;
+
+                case 4:
+                    $max = 360;
+                    break;
+
+                case 7:
+                    $max = 1;
+                    break;
+
+                default:
+                    $max = 100;
+            }
+
+            $scale = $scale / 100;
+
+            if ($scale < 0) {
+                return $base * $scale + $base;
+            }
+
+            return ($max - $base) * $scale + $base;
+        });
+    }
+
+    protected static $libIeHexStr = array('color');
+    protected function libIeHexStr($args)
+    {
+        $color = $this->coerceColor($args[0]);
+        $color[4] = isset($color[4]) ? round(255*$color[4]) : 255;
+
+        return sprintf('#%02X%02X%02X%02X', $color[4], $color[1], $color[2], $color[3]);
+    }
+
+    protected static $libRed = array('color');
+    protected function libRed($args)
+    {
+        $color = $this->coerceColor($args[0]);
+
+        return $color[1];
+    }
+
+    protected static $libGreen = array('color');
+    protected function libGreen($args)
+    {
+        $color = $this->coerceColor($args[0]);
+
+        return $color[2];
+    }
+
+    protected static $libBlue = array('color');
+    protected function libBlue($args)
+    {
+        $color = $this->coerceColor($args[0]);
+
+        return $color[3];
+    }
+
+    protected static $libAlpha = array('color');
+    protected function libAlpha($args)
+    {
+        if ($color = $this->coerceColor($args[0])) {
+            return isset($color[4]) ? $color[4] : 1;
+        }
+
+        // this might be the IE function, so return value unchanged
+        return null;
+    }
+
+    protected static $libOpacity = array('color');
+    protected function libOpacity($args)
+    {
+        $value = $args[0];
+
+        if ($value[0] === 'number') {
+            return null;
+        }
+
+        return $this->libAlpha($args);
+    }
+
+    // mix two colors
+    protected static $libMix = array('color-1', 'color-2', 'weight');
+    protected function libMix($args)
+    {
+        list($first, $second, $weight) = $args;
+
+        $first = $this->assertColor($first);
+        $second = $this->assertColor($second);
+
+        if (! isset($weight)) {
+            $weight = 0.5;
+        } else {
+            $weight = $this->coercePercent($weight);
+        }
+
+        $firstAlpha = isset($first[4]) ? $first[4] : 1;
+        $secondAlpha = isset($second[4]) ? $second[4] : 1;
+
+        $w = $weight * 2 - 1;
+        $a = $firstAlpha - $secondAlpha;
+
+        $w1 = (($w * $a === -1 ? $w : ($w + $a) / (1 + $w * $a)) + 1) / 2.0;
+        $w2 = 1.0 - $w1;
+
+        $new = array('color',
+            $w1 * $first[1] + $w2 * $second[1],
+            $w1 * $first[2] + $w2 * $second[2],
+            $w1 * $first[3] + $w2 * $second[3],
+        );
+
+        if ($firstAlpha != 1.0 || $secondAlpha != 1.0) {
+            $new[] = $firstAlpha * $weight + $secondAlpha * ($weight - 1);
+        }
+
+        return $this->fixColor($new);
+    }
+
+    protected static $libHsl = array('hue', 'saturation', 'lightness');
+    protected function libHsl($args)
+    {
+        list($h, $s, $l) = $args;
+
+        return $this->toRGB($h[1], $s[1], $l[1]);
+    }
+
+    protected static $libHsla = array('hue', 'saturation',
+        'lightness', 'alpha');
+    protected function libHsla($args)
+    {
+        list($h, $s, $l, $a) = $args;
+
+        $color = $this->toRGB($h[1], $s[1], $l[1]);
+        $color[4] = $a[1];
+
+        return $color;
+    }
+
+    protected static $libHue = array('color');
+    protected function libHue($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+        return array('number', $hsl[1], 'deg');
+    }
+
+    protected static $libSaturation = array('color');
+    protected function libSaturation($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+        return array('number', $hsl[2], '%');
+    }
+
+    protected static $libLightness = array('color');
+    protected function libLightness($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
+
+        return array('number', $hsl[3], '%');
+    }
+
+    protected function adjustHsl($color, $idx, $amount)
+    {
+        $hsl = $this->toHSL($color[1], $color[2], $color[3]);
+        $hsl[$idx] += $amount;
+        $out = $this->toRGB($hsl[1], $hsl[2], $hsl[3]);
+
+        if (isset($color[4])) {
+            $out[4] = $color[4];
+        }
+
+        return $out;
+    }
+
+    protected static $libAdjustHue = array('color', 'degrees');
+    protected function libAdjustHue($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $degrees = $this->assertNumber($args[1]);
+
+        return $this->adjustHsl($color, 1, $degrees);
+    }
+
+    protected static $libLighten = array('color', 'amount');
+    protected function libLighten($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $amount = Util::checkRange('amount', new Range(0, 100), $args[1], '%');
+
+        return $this->adjustHsl($color, 3, $amount);
+    }
+
+    protected static $libDarken = array('color', 'amount');
+    protected function libDarken($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $amount = Util::checkRange('amount', new Range(0, 100), $args[1], '%');
+
+        return $this->adjustHsl($color, 3, -$amount);
+    }
+
+    protected static $libSaturate = array('color', 'amount');
+    protected function libSaturate($args)
+    {
+        $value = $args[0];
+
+        if ($value[0] === 'number') {
+            return null;
+        }
+
+        $color = $this->assertColor($value);
+        $amount = 100*$this->coercePercent($args[1]);
+
+        return $this->adjustHsl($color, 2, $amount);
+    }
+
+    protected static $libDesaturate = array('color', 'amount');
+    protected function libDesaturate($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $amount = 100*$this->coercePercent($args[1]);
+
+        return $this->adjustHsl($color, 2, -$amount);
+    }
+
+    protected static $libGrayscale = array('color');
+    protected function libGrayscale($args)
+    {
+        $value = $args[0];
+
+        if ($value[0] === 'number') {
+            return null;
+        }
+
+        return $this->adjustHsl($this->assertColor($value), 2, -100);
+    }
+
+    protected static $libComplement = array('color');
+    protected function libComplement($args)
+    {
+        return $this->adjustHsl($this->assertColor($args[0]), 1, 180);
+    }
+
+    protected static $libInvert = array('color');
+    protected function libInvert($args)
+    {
+        $value = $args[0];
+
+        if ($value[0] === 'number') {
+            return null;
+        }
+
+        $color = $this->assertColor($value);
+        $color[1] = 255 - $color[1];
+        $color[2] = 255 - $color[2];
+        $color[3] = 255 - $color[3];
+
+        return $color;
+    }
+
+    // increases opacity by amount
+    protected static $libOpacify = array('color', 'amount');
+    protected function libOpacify($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $amount = $this->coercePercent($args[1]);
+
+        $color[4] = (isset($color[4]) ? $color[4] : 1) + $amount;
+        $color[4] = min(1, max(0, $color[4]));
+
+        return $color;
+    }
+
+    protected static $libFadeIn = array('color', 'amount');
+    protected function libFadeIn($args)
+    {
+        return $this->libOpacify($args);
+    }
+
+    // decreases opacity by amount
+    protected static $libTransparentize = array('color', 'amount');
+    protected function libTransparentize($args)
+    {
+        $color = $this->assertColor($args[0]);
+        $amount = $this->coercePercent($args[1]);
+
+        $color[4] = (isset($color[4]) ? $color[4] : 1) - $amount;
+        $color[4] = min(1, max(0, $color[4]));
+
+        return $color;
+    }
+
+    protected static $libFadeOut = array('color', 'amount');
+    protected function libFadeOut($args)
+    {
+        return $this->libTransparentize($args);
+    }
+
+    protected static $libUnquote = array('string');
+    protected function libUnquote($args)
+    {
+        $str = $args[0];
+
+        if ($str[0] === 'string') {
+            $str[1] = '';
+        }
+
+        return $str;
+    }
+
+    protected static $libQuote = array('string');
+    protected function libQuote($args)
+    {
+        $value = $args[0];
+
+        if ($value[0] === 'string' && ! empty($value[1])) {
+            return $value;
+        }
+
+        return array('string', '"', array($value));
+    }
+
+    protected static $libPercentage = array('value');
+    protected function libPercentage($args)
+    {
+        return array('number',
+            $this->coercePercent($args[0]) * 100,
+            '%');
+    }
+
+    protected static $libRound = array('value');
+    protected function libRound($args)
+    {
+        $num = $args[0];
+        $num[1] = round($num[1]);
+
+        return $num;
+    }
+
+    protected static $libFloor = array('value');
+    protected function libFloor($args)
+    {
+        $num = $args[0];
+        $num[1] = floor($num[1]);
+
+        return $num;
+    }
+
+    protected static $libCeil = array('value');
+    protected function libCeil($args)
+    {
+        $num = $args[0];
+        $num[1] = ceil($num[1]);
+
+        return $num;
+    }
+
+    protected static $libAbs = array('value');
+    protected function libAbs($args)
+    {
+        $num = $args[0];
+        $num[1] = abs($num[1]);
+
+        return $num;
+    }
+
+    protected function libMin($args)
+    {
+        $numbers = $this->getNormalizedNumbers($args);
+        $min = null;
+
+        foreach ($numbers as $key => $number) {
+            if (null === $min || $number[1] <= $min[1]) {
+                $min = array($key, $number[1]);
+            }
+        }
+
+        return $args[$min[0]];
+    }
+
+    protected function libMax($args)
+    {
+        $numbers = $this->getNormalizedNumbers($args);
+        $max = null;
+
+        foreach ($numbers as $key => $number) {
+            if (null === $max || $number[1] >= $max[1]) {
+                $max = array($key, $number[1]);
+            }
+        }
+
+        return $args[$max[0]];
+    }
+
+    /**
+     * Helper to normalize args containing numbers
+     *
+     * @param array $args
+     *
+     * @return array
+     */
+    protected function getNormalizedNumbers($args)
+    {
+        $unit = null;
+        $originalUnit = null;
+        $numbers = array();
+
+        foreach ($args as $key => $item) {
+            if ('number' !== $item[0]) {
+                $this->throwError('%s is not a number', $item[0]);
+            }
+
+            $number = $this->normalizeNumber($item);
+
+            if (null === $unit) {
+                $unit = $number[2];
+                $originalUnit = $item[2];
+            } elseif ($unit !== $number[2]) {
+                $this->throwError('Incompatible units: "%s" and "%s".', $originalUnit, $item[2]);
+            }
+
+            $numbers[$key] = $number;
+        }
+
+        return $numbers;
+    }
+
+    protected static $libLength = array('list');
+    protected function libLength($args)
+    {
+        $list = $this->coerceList($args[0]);
+
+        return count($list[2]);
+    }
+
+    // TODO: need a way to declare this built-in as varargs
+    //protected static $libListSeparator = array('list...');
+    protected function libListSeparator($args)
+    {
+        if (count($args) > 1) {
+            return 'comma';
+        }
+
+        $list = $this->coerceList($args[0]);
+
+        if (count($list[2]) <= 1) {
+            return 'space';
+        }
+
+        if ($list[1] === ',') {
+            return 'comma';
+        }
+
+        return 'space';
+    }
+
+    protected static $libNth = array('list', 'n');
+    protected function libNth($args)
+    {
+        $list = $this->coerceList($args[0]);
+        $n = $this->assertNumber($args[1]) - 1;
+
+        return isset($list[2][$n]) ? $list[2][$n] : self::$defaultValue;
+    }
+
+    protected static $libSetNth = array('list', 'n', 'value');
+    protected function libSetNth($args)
+    {
+        $list = $this->coerceList($args[0]);
+        $n = $this->assertNumber($args[1]) - 1;
+
+        if (! isset($list[2][$n])) {
+            $this->throwError('Invalid argument for "n"');
+        }
+
+        $list[2][$n] = $args[2];
+
+        return $list;
+    }
+
+    protected static $libMapGet = array('map', 'key');
+    protected function libMapGet($args)
+    {
+        $map = $this->assertMap($args[0]);
+
+        $key = $this->compileStringContent($this->coerceString($args[1]));
+
+        for ($i = count($map[1]) - 1; $i >= 0; $i--) {
+            if ($key === $this->compileValue($map[1][$i])) {
+                return $map[2][$i];
+            }
+        }
+
+        return self::$null;
+    }
+
+    protected static $libMapKeys = array('map');
+    protected function libMapKeys($args)
+    {
+        $map = $this->assertMap($args[0]);
+
+        $keys = $map[1];
+
+        return array('list', ',', $keys);
+    }
+
+    protected static $libMapValues = array('map');
+    protected function libMapValues($args)
+    {
+        $map = $this->assertMap($args[0]);
+
+        $values = $map[2];
+
+        return array('list', ',', $values);
+    }
+
+    protected static $libMapRemove = array('map', 'key');
+    protected function libMapRemove($args)
+    {
+        $map = $this->assertMap($args[0]);
+
+        $key = $this->compileStringContent($this->coerceString($args[1]));
+
+        for ($i = count($map[1]) - 1; $i >= 0; $i--) {
+            if ($key === $this->compileValue($map[1][$i])) {
+                array_splice($map[1], $i, 1);
+                array_splice($map[2], $i, 1);
+            }
+        }
+
+        return $map;
+    }
+
+    protected static $libMapHasKey = array('map', 'key');
+    protected function libMapHasKey($args)
+    {
+        $map = $this->assertMap($args[0]);
+
+        $key = $this->compileStringContent($this->coerceString($args[1]));
+
+        for ($i = count($map[1]) - 1; $i >= 0; $i--) {
+            if ($key === $this->compileValue($map[1][$i])) {
+                return self::$true;
+            }
+        }
+
+        return self::$false;
+    }
+
+    protected static $libMapMerge = array('map-1', 'map-2');
+    protected function libMapMerge($args)
+    {
+        $map1 = $this->assertMap($args[0]);
+        $map2 = $this->assertMap($args[1]);
+
+        return array('map', array_merge($map1[1], $map2[1]), array_merge($map1[2], $map2[2]));
+    }
+
+    protected function listSeparatorForJoin($list1, $sep)
+    {
+        if (! isset($sep)) {
+            return $list1[1];
+        }
+
+        switch ($this->compileValue($sep)) {
+            case 'comma':
+                return ',';
+
+            case 'space':
+                return '';
+
+            default:
+                return $list1[1];
+        }
+    }
+
+    protected static $libJoin = array('list1', 'list2', 'separator');
+    protected function libJoin($args)
+    {
+        list($list1, $list2, $sep) = $args;
+
+        $list1 = $this->coerceList($list1, ' ');
+        $list2 = $this->coerceList($list2, ' ');
+        $sep = $this->listSeparatorForJoin($list1, $sep);
+
+        return array('list', $sep, array_merge($list1[2], $list2[2]));
+    }
+
+    protected static $libAppend = array('list', 'val', 'separator');
+    protected function libAppend($args)
+    {
+        list($list1, $value, $sep) = $args;
+
+        $list1 = $this->coerceList($list1, ' ');
+        $sep = $this->listSeparatorForJoin($list1, $sep);
+
+        return array('list', $sep, array_merge($list1[2], array($value)));
+    }
+
+    protected function libZip($args)
+    {
+        foreach ($args as $arg) {
+            $this->assertList($arg);
+        }
+
+        $lists = array();
+        $firstList = array_shift($args);
+
+        foreach ($firstList[2] as $key => $item) {
+            $list = array('list', '', array($item));
+
+            foreach ($args as $arg) {
+                if (isset($arg[2][$key])) {
+                    $list[2][] = $arg[2][$key];
+                } else {
+                    break 2;
+                }
+            }
+            $lists[] = $list;
+        }
+
+        return array('list', ',', $lists);
+    }
+
+    protected static $libTypeOf = array('value');
+    protected function libTypeOf($args)
+    {
+        $value = $args[0];
+
+        switch ($value[0]) {
+            case 'keyword':
+                if ($value === self::$true || $value === self::$false) {
+                    return 'bool';
+                }
+
+                if ($this->coerceColor($value)) {
+                    return 'color';
+                }
+
+                // fall-thru
+            case 'function':
+                return 'string';
+
+            case 'list':
+                if (isset($value[3]) && $value[3]) {
+                    return 'arglist';
+                }
+
+                // fall-thru
+            default:
+                return $value[0];
+        }
+    }
+
+    protected static $libUnit = array('number');
+    protected function libUnit($args)
+    {
+        $num = $args[0];
+
+        if ($num[0] === 'number') {
+            return array('string', '"', array($num[2]));
+        }
+
+        return '';
+    }
+
+    protected static $libUnitless = array('number');
+    protected function libUnitless($args)
+    {
+        $value = $args[0];
+
+        return $value[0] === 'number' && empty($value[2]);
+    }
+
+    protected static $libComparable = array('number-1', 'number-2');
+    protected function libComparable($args)
+    {
+        list($number1, $number2) = $args;
+
+        if (! isset($number1[0]) || $number1[0] !== 'number' || ! isset($number2[0]) || $number2[0] !== 'number') {
+            $this->throwError('Invalid argument(s) for "comparable"');
+        }
+
+        $number1 = $this->normalizeNumber($number1);
+        $number2 = $this->normalizeNumber($number2);
+
+        return $number1[2] === $number2[2] || $number1[2] === '' || $number2[2] === '';
+    }
+
+    protected static $libStrIndex = array('string', 'substring');
+    protected function libStrIndex($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $stringContent = $this->compileStringContent($string);
+
+        $substring = $this->coerceString($args[1]);
+        $substringContent = $this->compileStringContent($substring);
+
+        $result = strpos($stringContent, $substringContent);
+
+        return $result === false ? self::$null : array('number', $result + 1, '');
+    }
+
+    protected static $libStrInsert = array('string', 'insert', 'index');
+    protected function libStrInsert($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $stringContent = $this->compileStringContent($string);
+
+        $insert = $this->coerceString($args[1]);
+        $insertContent = $this->compileStringContent($insert);
+
+        list(, $index) = $args[2];
+
+        $string[2] = array(substr_replace($stringContent, $insertContent, $index - 1, 0));
+
+        return $string;
+    }
+
+    protected static $libStrLength = array('string');
+    protected function libStrLength($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $stringContent = $this->compileStringContent($string);
+
+        return array('number', strlen($stringContent), '');
+    }
+
+    protected static $libStrSlice = array('string', 'start-at', 'end-at');
+    protected function libStrSlice($args)
+    {
+        if ($args[2][1] == 0) {
+            return self::$emptyString;
+        }
+
+        $string = $this->coerceString($args[0]);
+        $stringContent = $this->compileStringContent($string);
+
+        $start = (int) $args[1][1] ?: 1;
+        $end = (int) $args[2][1];
+
+        $string[2] = array(substr($stringContent, $start - 1, $end < 0 ? $end : $end - $start + 1));
+
+        return $string;
+    }
+
+    protected static $libToLowerCase = array('string');
+    protected function libToLowerCase($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $stringContent = $this->compileStringContent($string);
+
+        $string[2] = array(mb_strtolower($stringContent));
+
+        return $string;
+    }
+
+    protected static $libToUpperCase = array('string');
+    protected function libToUpperCase($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $stringContent = $this->compileStringContent($string);
+
+        $string[2] = array(mb_strtoupper($stringContent));
+
+        return $string;
+    }
+
+    protected static $libFeatureExists = array('feature');
+    protected function libFeatureExists($args)
+    {
+        /*
+         * The following features not not (yet) supported:
+         * - global-variable-shadowing
+         * - extend-selector-pseudoclass
+         * - units-level-3
+         * - at-error
+         */
+        return self::$false;
+    }
+
+    protected static $libFunctionExists = array('name');
+    protected function libFunctionExists($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $name = $this->compileStringContent($string);
+
+        // user defined functions
+        if ($this->has(self::$namespaces['function'] . $name)) {
+            return self::$true;
+        }
+
+        $name = $this->normalizeName($name);
+
+        if (isset($this->userFunctions[$name])) {
+            return self::$true;
+        }
+
+        // built-in functions
+        $f = $this->getBuiltinFunction($name);
+
+        return $this->toBool(is_callable($f));
+    }
+
+    protected static $libGlobalVariableExists = array('name');
+    protected function libGlobalVariableExists($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $name = $this->compileStringContent($string);
+
+        return $this->has($name, $this->rootEnv) ? self::$true : self::$false;
+    }
+
+    protected static $libMixinExists = array('name');
+    protected function libMixinExists($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $name = $this->compileStringContent($string);
+
+        return $this->has(self::$namespaces['mixin'] . $name) ? self::$true : self::$false;
+    }
+
+    protected static $libVariableExists = array('name');
+    protected function libVariableExists($args)
+    {
+        $string = $this->coerceString($args[0]);
+        $name = $this->compileStringContent($string);
+
+        return $this->has($name) ? self::$true : self::$false;
+    }
+
+    /**
+     * Workaround IE7's content counter bug.
+     *
+     * @param array $args
+     */
+    protected function libCounter($args)
+    {
+        $list = array_map(array($this, 'compileValue'), $args);
+
+        return array('string', '', array('counter(' . implode(',', $list) . ')'));
+    }
+
+    protected function libRandom($args)
+    {
+        if (isset($args[0])) {
+            $n = $this->assertNumber($args[0]);
+
+            if ($n < 1) {
+                $this->throwError("limit must be greater than or equal to 1");
+            }
+
+            return array('number', mt_rand(1, $n), '');
+        }
+
+        return array('number', mt_rand(1, mt_getrandmax()), '');
+    }
+
+    protected function libUniqueId()
+    {
+        static $id;
+
+        if (! isset($id)) {
+            $id = mt_rand(0, pow(36, 8));
+        }
+
+        $id += mt_rand(0, 10) + 1;
+
+        return array('string', '', array('u' . str_pad(base_convert($id, 10, 36), 8, '0', STR_PAD_LEFT)));
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter.php
new file mode 100644
index 0000000000..5b035e1c2b
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter.php
@@ -0,0 +1,167 @@
+
+ */
+abstract class Formatter
+{
+    /**
+     * @var integer
+     */
+    public $indentLevel;
+
+    /**
+     * @var string
+     */
+    public $indentChar;
+
+    /**
+     * @var string
+     */
+    public $break;
+
+    /**
+     * @var string
+     */
+    public $open;
+
+    /**
+     * @var string
+     */
+    public $close;
+
+    /**
+     * @var string
+     */
+    public $tagSeparator;
+
+    /**
+     * @var string
+     */
+    public $assignSeparator;
+
+    abstract public function __construct();
+
+    /**
+     * Return indentation (whitespace)
+     *
+     * @param integer $n
+     *
+     * @return string
+     */
+    protected function indentStr($n = 0)
+    {
+        return str_repeat($this->indentChar, max($this->indentLevel + $n, 0));
+    }
+
+    /**
+     * Return property assignment
+     *
+     * @param string $name
+     * @param mixed  $value
+     *
+     * @return string
+     */
+    public function property($name, $value)
+    {
+        return rtrim($name) . $this->assignSeparator . $value . ';';
+    }
+
+    /**
+     * Strip semi-colon appended by property(); it's a separator, not a terminator
+     *
+     * @param array $lines
+     */
+    public function stripSemicolon(&$lines)
+    {
+    }
+
+    /**
+     * Output lines inside a block
+     *
+     * @param string    $inner
+     * @param \stdClass $block
+     */
+    protected function blockLines($inner, $block)
+    {
+        $glue = $this->break . $inner;
+        echo $inner . implode($glue, $block->lines);
+
+        if (! empty($block->children)) {
+            echo $this->break;
+        }
+    }
+
+    /**
+     * Output non-empty block
+     *
+     * @param \stdClass $block
+     */
+    protected function block($block)
+    {
+        if (empty($block->lines) && empty($block->children)) {
+            return;
+        }
+
+        $inner = $pre = $this->indentStr();
+
+        if (! empty($block->selectors)) {
+            echo $pre
+                . implode($this->tagSeparator, $block->selectors)
+                . $this->open . $this->break;
+
+            $this->indentLevel++;
+
+            $inner = $this->indentStr();
+        }
+
+        if (! empty($block->lines)) {
+            $this->blockLines($inner, $block);
+        }
+
+        foreach ($block->children as $child) {
+            $this->block($child);
+        }
+
+        if (! empty($block->selectors)) {
+            $this->indentLevel--;
+
+            if (empty($block->children)) {
+                echo $this->break;
+            }
+
+            echo $pre . $this->close . $this->break;
+        }
+    }
+
+    /**
+     * Entry point to formatting a block
+     *
+     * @param \stdClass $block An abstract syntax tree
+     *
+     * @return string
+     */
+    public function format($block)
+    {
+        ob_start();
+
+        $this->block($block);
+
+        $out = ob_get_clean();
+
+        return $out;
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compact.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compact.php
new file mode 100644
index 0000000000..29874c96c2
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compact.php
@@ -0,0 +1,44 @@
+
+ */
+class Compact extends Formatter
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function __construct()
+    {
+        $this->indentLevel = 0;
+        $this->indentChar = '';
+        $this->break = '';
+        $this->open = ' {';
+        $this->close = "}\n\n";
+        $this->tagSeparator = ',';
+        $this->assignSeparator = ':';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function indentStr($n = 0)
+    {
+        return ' ';
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compressed.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compressed.php
new file mode 100644
index 0000000000..c95b68b324
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Compressed.php
@@ -0,0 +1,89 @@
+
+ */
+class Compressed extends Formatter
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function __construct()
+    {
+        $this->indentLevel = 0;
+        $this->indentChar = '  ';
+        $this->break = '';
+        $this->open = '{';
+        $this->close = '}';
+        $this->tagSeparator = ',';
+        $this->assignSeparator = ':';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function indentStr($n = 0)
+    {
+        return '';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function stripSemicolon(&$lines)
+    {
+        if (($count = count($lines))
+            && substr($lines[$count - 1], -1) === ';'
+        ) {
+            $lines[$count - 1] = substr($lines[$count - 1], 0, -1);
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function blockLines($inner, $block)
+    {
+        $glue = $this->break . $inner;
+
+        foreach ($block->lines as $index => $line) {
+            if (substr($line, 0, 2) === '/*' && substr($line, 2, 1) !== '!') {
+                unset($block->lines[$index]);
+            } elseif (substr($line, 0, 3) === '/*!') {
+                $block->lines[$index] = '/*' . substr($line, 3);
+            }
+        }
+
+        echo $inner . implode($glue, $block->lines);
+
+        if (! empty($block->children)) {
+            echo $this->break;
+        }
+    }
+
+    /**
+     * {@inherit}
+     */
+    public function format($block)
+    {
+        return parent::format($block);
+
+        // TODO: we need to fix the 2 "compressed" tests where the "close" is applied
+        return trim(str_replace(';}', '}', parent::format($block)));
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Crunched.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Crunched.php
new file mode 100644
index 0000000000..1227c12279
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Crunched.php
@@ -0,0 +1,76 @@
+
+ */
+class Crunched extends Formatter
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function __construct()
+    {
+        $this->indentLevel = 0;
+        $this->indentChar = '  ';
+        $this->break = '';
+        $this->open = '{';
+        $this->close = '}';
+        $this->tagSeparator = ',';
+        $this->assignSeparator = ':';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function indentStr($n = 0)
+    {
+        return '';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function stripSemicolon(&$lines)
+    {
+        if (($count = count($lines))
+            && substr($lines[$count - 1], -1) === ';'
+        ) {
+            $lines[$count - 1] = substr($lines[$count - 1], 0, -1);
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function blockLines($inner, $block)
+    {
+        $glue = $this->break . $inner;
+
+        foreach ($block->lines as $index => $line) {
+            if (substr($line, 0, 2) === '/*') {
+                unset($block->lines[$index]);
+            }
+        }
+
+        echo $inner . implode($glue, $block->lines);
+
+        if (! empty($block->children)) {
+            echo $this->break;
+        }
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Expanded.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Expanded.php
new file mode 100644
index 0000000000..fbf85c1e18
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Expanded.php
@@ -0,0 +1,56 @@
+
+ */
+class Expanded extends Formatter
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function __construct()
+    {
+        $this->indentLevel = 0;
+        $this->indentChar = '  ';
+        $this->break = "\n";
+        $this->open = ' {';
+        $this->close = '}';
+        $this->tagSeparator = ', ';
+        $this->assignSeparator = ': ';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function blockLines($inner, $block)
+    {
+        $glue = $this->break . $inner;
+
+        foreach ($block->lines as $index => $line) {
+            if (substr($line, 0, 2) === '/*') {
+                $block->lines[$index] = preg_replace('/(\r|\n)+/', $glue, $line);
+            }
+        }
+
+        echo $inner . implode($glue, $block->lines);
+
+        if (empty($block->selectors) || ! empty($block->children)) {
+            echo $this->break;
+        }
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Nested.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Nested.php
new file mode 100644
index 0000000000..bd2c4d2136
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Formatter/Nested.php
@@ -0,0 +1,145 @@
+
+ */
+class Nested extends Formatter
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function __construct()
+    {
+        $this->indentLevel = 0;
+        $this->indentChar = '  ';
+        $this->break = "\n";
+        $this->open = ' {';
+        $this->close = ' }';
+        $this->tagSeparator = ', ';
+        $this->assignSeparator = ': ';
+    }
+
+    /**
+     * Adjust the depths of all children, depth first
+     *
+     * @param \stdClass $block
+     */
+    public function adjustAllChildren($block)
+    {
+        // flatten empty nested blocks
+        $children = array();
+        foreach ($block->children as $i => $child) {
+            if (empty($child->lines) && empty($child->children)) {
+                if (isset($block->children[$i + 1])) {
+                    $block->children[$i + 1]->depth = $child->depth;
+                }
+                continue;
+            }
+            $children[] = $child;
+        }
+
+        $count = count($children);
+        for ($i = 0; $i < $count; $i++) {
+            $depth = $children[$i]->depth;
+            $j = $i + 1;
+            if (isset($children[$j]) && $depth < $children[$j]->depth) {
+                $childDepth = $children[$j]->depth;
+                for (; $j < $count; $j++) {
+                    if ($depth < $children[$j]->depth && $childDepth >= $children[$j]->depth) {
+                        $children[$j]->depth = $depth + 1;
+                    }
+                }
+            }
+        }
+
+        $block->children = $children;
+
+        // make relative to parent
+        foreach ($block->children as $child) {
+            $this->adjustAllChildren($child);
+            $child->depth = $child->depth - $block->depth;
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function blockLines($inner, $block)
+    {
+        $glue = $this->break . $inner;
+
+        foreach ($block->lines as $index => $line) {
+            if (substr($line, 0, 2) === '/*') {
+                $block->lines[$index] = preg_replace('/(\r|\n)+/', $glue, $line);
+            }
+        }
+
+        echo $inner . implode($glue, $block->lines);
+
+        if (! empty($block->children)) {
+            echo $this->break;
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function block($block)
+    {
+        if ($block->type === 'root') {
+            $this->adjustAllChildren($block);
+        }
+
+        $inner = $pre = $this->indentStr($block->depth - 1);
+        if (! empty($block->selectors)) {
+            echo $pre .
+                implode($this->tagSeparator, $block->selectors) .
+                $this->open . $this->break;
+            $this->indentLevel++;
+            $inner = $this->indentStr($block->depth - 1);
+        }
+
+        if (! empty($block->lines)) {
+            $this->blockLines($inner, $block);
+        }
+
+        foreach ($block->children as $i => $child) {
+            $this->block($child);
+
+            if ($i < count($block->children) - 1) {
+                echo $this->break;
+
+                if (isset($block->children[$i + 1])) {
+                    $next = $block->children[$i + 1];
+                    if ($next->depth === max($block->depth, 1) && $child->depth >= $next->depth) {
+                        echo $this->break;
+                    }
+                }
+            }
+        }
+
+        if (! empty($block->selectors)) {
+            $this->indentLevel--;
+            echo $this->close;
+        }
+
+        if ($block->type === 'root') {
+            echo $this->break;
+        }
+    }
+}
diff --git a/wcfsetup/install/files/lib/system/style/scssphp/src/Parser.php b/wcfsetup/install/files/lib/system/style/scssphp/src/Parser.php
new file mode 100644
index 0000000000..8b27a27e4e
--- /dev/null
+++ b/wcfsetup/install/files/lib/system/style/scssphp/src/Parser.php
@@ -0,0 +1,2342 @@
+
+ */
+class Parser
+{
+    const SOURCE_POSITION = -1;
+    const SOURCE_PARSER   = -2;
+
+    /**
+     * @var array
+     */
+    protected static $precedence = array(
+        '=' => 0,
+        'or' => 1,
+        'and' => 2,
+        '==' => 3,
+        '!=' => 3,
+        '<=' => 4,
+        '>=' => 4,
+        '<' => 4,
+        '>' => 4,
+        '+' => 5,
+        '-' => 5,
+        '*' => 6,
+        '/' => 6,
+        '%' => 6,
+    );
+
+    /**
+     * @var array
+     */
+    protected static $operators = array(
+        '+',
+        '-',
+        '*',
+        '/',
+        '%',
+        '==',
+        '!=',
+        '<=',
+        '>=',
+        '<',
+        '>',
+        'and',
+        'or',
+    );
+
+    protected static $operatorStr;
+    protected static $whitePattern;
+    protected static $commentMulti;
+
+    protected static $commentSingle = '//';
+    protected static $commentMultiLeft = '/*';
+    protected static $commentMultiRight = '*/';
+
+    private $sourceName;
+    private $rootParser;
+    private $charset;
+    private $count;
+    private $env;
+    private $inParens;
+    private $eatWhiteDefault;
+    private $buffer;
+
+    /**
+     * Constructor
+     *
+     * @param string  $sourceName
+     * @param boolean $rootParser
+     */
+    public function __construct($sourceName = null, $rootParser = true)
+    {
+        $this->sourceName = $sourceName;
+        $this->rootParser = $rootParser;
+        $this->charset = null;
+
+        if (empty(self::$operatorStr)) {
+            self::$operatorStr = $this->makeOperatorStr(self::$operators);
+
+            $commentSingle = $this->pregQuote(self::$commentSingle);
+            $commentMultiLeft = $this->pregQuote(self::$commentMultiLeft);
+            $commentMultiRight = $this->pregQuote(self::$commentMultiRight);
+            self::$commentMulti = $commentMultiLeft . '.*?' . $commentMultiRight;
+            self::$whitePattern = '/' . $commentSingle . '[^\n]*\s*|(' . self::$commentMulti . ')\s*|\s+/Ais';
+        }
+    }
+
+    /**
+     * Make operator regex
+     *
+     * @param array $operators
+     *
+     * @return string
+     */
+    protected static function makeOperatorStr($operators)
+    {
+        return '('
+            . implode('|', array_map(array('Leafo\ScssPhp\Parser', 'pregQuote'), $operators))
+            . ')';
+    }
+
+    /**
+     * Parser buffer
+     *
+     * @param string $buffer;
+     *
+     * @return \stdClass
+     */
+    public function parse($buffer)
+    {
+        $this->count           = 0;
+        $this->env             = null;
+        $this->inParens        = false;
+        $this->eatWhiteDefault = true;
+        $this->buffer          = $buffer;
+
+        $this->pushBlock(null); // root block
+
+        $this->whitespace();
+        $this->pushBlock(null);
+        $this->popBlock();
+
+        while (false !== $this->parseChunk()) {
+            ;
+        }
+
+        if ($this->count !== strlen($this->buffer)) {
+            $this->throwParseError();
+        }
+
+        if (! empty($this->env->parent)) {
+            $this->throwParseError('unclosed block');
+        }
+
+        if ($this->charset) {
+            array_unshift($this->env->children, $this->charset);
+        }
+
+        $this->env->isRoot    = true;
+
+        return $this->env;
+    }
+
+    /**
+     * Parse a value or value list
+     *
+     * @param string $buffer
+     * @param string $out
+     *
+     * @return boolean
+     */
+    public function parseValue($buffer, &$out)
+    {
+        $this->count           = 0;
+        $this->env             = null;
+        $this->inParens        = false;
+        $this->eatWhiteDefault = true;
+        $this->buffer          = (string) $buffer;
+
+        return $this->valueList($out);
+    }
+
+    /**
+     * Parse a selector or selector list
+     *
+     * @param string $buffer
+     * @param string $out
+     *
+     * @return boolean
+     */
+    public function parseSelector($buffer, &$out)
+    {
+        $this->count           = 0;
+        $this->env             = null;
+        $this->inParens        = false;
+        $this->eatWhiteDefault = true;
+        $this->buffer          = (string) $buffer;
+
+        return $this->selectors($out);
+    }
+
+    /**
+     * Parse a single chunk off the head of the buffer and append it to the
+     * current parse environment.
+     *
+     * Returns false when the buffer is empty, or when there is an error.
+     *
+     * This function is called repeatedly until the entire document is
+     * parsed.
+     *
+     * This parser is most similar to a recursive descent parser. Single
+     * functions represent discrete grammatical rules for the language, and
+     * they are able to capture the text that represents those rules.
+     *
+     * Consider the function Compiler::keyword(). (All parse functions are
+     * structured the same.)
+     *
+     * The function takes a single reference argument. When calling the
+     * function it will attempt to match a keyword on the head of the buffer.
+     * If it is successful, it will place the keyword in the referenced
+     * argument, advance the position in the buffer, and return true. If it
+     * fails then it won't advance the buffer and it will return false.
+     *
+     * All of these parse functions are powered by Compiler::match(), which behaves
+     * the same way, but takes a literal regular expression. Sometimes it is
+     * more convenient to use match instead of creating a new function.
+     *
+     * Because of the format of the functions, to parse an entire string of
+     * grammatical rules, you can chain them together using &&.
+     *
+     * But, if some of the rules in the chain succeed before one fails, then
+     * the buffer position will be left at an invalid state. In order to
+     * avoid this, Compiler::seek() is used to remember and set buffer positions.
+     *
+     * Before parsing a chain, use $s = $this->seek() to remember the current
+     * position into $s. Then if a chain fails, use $this->seek($s) to
+     * go back where we started.
+     *
+     * @return boolean
+     */
+    protected function parseChunk()
+    {
+        $s = $this->seek();
+
+        // the directives
+        if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] === '@') {
+            if ($this->literal('@media') && $this->mediaQueryList($mediaQueryList) && $this->literal('{')) {
+                $media = $this->pushSpecialBlock('media', $s);
+                $media->queryList = $mediaQueryList[2];
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@mixin') &&
+                $this->keyword($mixinName) &&
+                ($this->argumentDef($args) || true) &&
+                $this->literal('{')
+            ) {
+                $mixin = $this->pushSpecialBlock('mixin', $s);
+                $mixin->name = $mixinName;
+                $mixin->args = $args;
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@include') &&
+                $this->keyword($mixinName) &&
+                ($this->literal('(') &&
+                    ($this->argValues($argValues) || true) &&
+                    $this->literal(')') || true) &&
+                ($this->end() ||
+                    $this->literal('{') && $hasBlock = true)
+            ) {
+                $child = array('include',
+                    $mixinName, isset($argValues) ? $argValues : null, null);
+
+                if (! empty($hasBlock)) {
+                    $include = $this->pushSpecialBlock('include', $s);
+                    $include->child = $child;
+                } else {
+                    $this->append($child, $s);
+                }
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@import') &&
+                $this->valueList($importPath) &&
+                $this->end()
+            ) {
+                $this->append(array('import', $importPath), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@import') &&
+                $this->url($importPath) &&
+                $this->end()
+            ) {
+                $this->append(array('import', $importPath), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@extend') &&
+                $this->selectors($selector) &&
+                $this->end()
+            ) {
+                $this->append(array('extend', $selector), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@function') &&
+                $this->keyword($fnName) &&
+                $this->argumentDef($args) &&
+                $this->literal('{')
+            ) {
+                $func = $this->pushSpecialBlock('function', $s);
+                $func->name = $fnName;
+                $func->args = $args;
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@return') && $this->valueList($retVal) && $this->end()) {
+                $this->append(array('return', $retVal), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@each') &&
+                $this->genericList($varNames, 'variable', ',', false) &&
+                $this->literal('in') &&
+                $this->valueList($list) &&
+                $this->literal('{')
+            ) {
+                $each = $this->pushSpecialBlock('each', $s);
+
+                foreach ($varNames[2] as $varName) {
+                    $each->vars[] = $varName[1];
+                }
+
+                $each->list = $list;
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@while') &&
+                $this->expression($cond) &&
+                $this->literal('{')
+            ) {
+                $while = $this->pushSpecialBlock('while', $s);
+                $while->cond = $cond;
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@for') &&
+                $this->variable($varName) &&
+                $this->literal('from') &&
+                $this->expression($start) &&
+                ($this->literal('through') ||
+                    ($forUntil = true && $this->literal('to'))) &&
+                $this->expression($end) &&
+                $this->literal('{')
+            ) {
+                $for = $this->pushSpecialBlock('for', $s);
+                $for->var = $varName[1];
+                $for->start = $start;
+                $for->end = $end;
+                $for->until = isset($forUntil);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@if') && $this->valueList($cond) && $this->literal('{')) {
+                $if = $this->pushSpecialBlock('if', $s);
+                $if->cond = $cond;
+                $if->cases = array();
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@debug') &&
+                $this->valueList($value) &&
+                $this->end()
+            ) {
+                $this->append(array('debug', $value), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@warn') &&
+                $this->valueList($value) &&
+                $this->end()
+            ) {
+                $this->append(array('warn', $value), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@error') &&
+                $this->valueList($value) &&
+                $this->end()
+            ) {
+                $this->append(array('error', $value), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            if ($this->literal('@content') && $this->end()) {
+                $this->append(array('mixin_content'), $s);
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            $last = $this->last();
+
+            if (isset($last) && $last[0] === 'if') {
+                list(, $if) = $last;
+
+                if ($this->literal('@else')) {
+                    if ($this->literal('{')) {
+                        $else = $this->pushSpecialBlock('else', $s);
+                    } elseif ($this->literal('if') && $this->valueList($cond) && $this->literal('{')) {
+                        $else = $this->pushSpecialBlock('elseif', $s);
+                        $else->cond = $cond;
+                    }
+
+                    if (isset($else)) {
+                        $else->dontAppend = true;
+                        $if->cases[] = $else;
+
+                        return true;
+                    }
+                }
+
+                $this->seek($s);
+            }
+
+            // only retain the first @charset directive encountered
+            if ($this->literal('@charset') &&
+                $this->valueList($charset) && $this->end()
+            ) {
+                if (! isset($this->charset)) {
+                    $statement = array('charset', $charset);
+
+                    $statement[self::SOURCE_POSITION] = $s;
+
+                    if (! $this->rootParser) {
+                        $statement[self::SOURCE_PARSER] = $this;
+                    }
+
+                    $this->charset = $statement;
+                }
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            // doesn't match built in directive, do generic one
+            if ($this->literal('@', false) && $this->keyword($dirName) &&
+                ($this->variable($dirValue) || $this->openString('{', $dirValue) || true) &&
+                $this->literal('{')
+            ) {
+                $directive = $this->pushSpecialBlock('directive', $s);
+                $directive->name = $dirName;
+
+                if (isset($dirValue)) {
+                    $directive->value = $dirValue;
+                }
+
+                return true;
+            }
+
+            $this->seek($s);
+
+            return false;
+        }
+
+        // property shortcut
+        // captures most properties before having to parse a selector
+        if ($this->keyword($name, false) &&
+            $this->literal(': ') &&
+            $this->valueList($value) &&
+            $this->end()
+        ) {
+            $name = array('string', '', array($name));
+            $this->append(array('assign', $name, $value), $s);
+
+            return true;
+        }
+
+        $this->seek($s);
+
+        // variable assigns
+        if ($this->variable($name) &&
+            $this->literal(':') &&
+            $this->valueList($value) && $this->end()
+        ) {
+            // check for '!flag'
+            $assignmentFlag = $this->stripAssignmentFlag($value);
+            $this->append(array('assign', $name, $value, $assignmentFlag), $s);
+
+            return true;
+        }
+
+        $this->seek($s);
+
+        // misc
+        if ($this->literal('-->')) {
+            return true;
+        }
+
+        // opening css block
+        if ($this->selectors($selectors) && $this->literal('{')) {
+            $b = $this->pushBlock($selectors, $s);
+
+            return true;
+        }
+
+        $this->seek($s);
+
+        // property assign, or nested assign
+        if ($this->propertyName($name) && $this->literal(':')) {
+            $foundSomething = false;
+
+            if ($this->valueList($value)) {
+                $this->append(array('assign', $name, $value), $s);
+                $foundSomething = true;
+            }
+
+            if ($this->literal('{')) {
+                $propBlock = $this->pushSpecialBlock('nestedprop', $s);
+                $propBlock->prefix = $name;
+                $foundSomething = true;
+            } elseif ($foundSomething) {
+                $foundSomething = $this->end();
+            }
+
+            if ($foundSomething) {
+                return true;
+            }
+        }
+
+        $this->seek($s);
+
+        // closing a block
+        if ($this->literal('}')) {
+            $block = $this->popBlock();
+
+            if (isset($block->type) && $block->type === 'include') {
+                $include = $block->child;
+                unset($block->child);
+                $include[3] = $block;
+                $this->append($include, $s);
+            } elseif (empty($block->dontAppend)) {
+                $type = isset($block->type) ? $block->type : 'block';
+                $this->append(array($type, $block), $s);
+            }
+
+            return true;
+        }
+
+        // extra stuff
+        if ($this->literal(';') ||
+            $this->literal('