src/CSSJanus.php
private static function fixLeftAndRight($css) {
		if (extension_loaded('mbstring')){
  			mb_internal_encoding("UTF-8");
  			mb_regex_encoding("UTF-8");
  			$css = mb_eregi_replace(trim(rtrim(self::$patterns['left'],'i'),'/'), self::$patterns['tmpToken'], $css);
  			$css = mb_eregi_replace(trim(rtrim(self::$patterns['right'],'i'),'/'), 'left', $css);
		}else{
  			$css = preg_replace(self::$patterns['left'], self::$patterns['tmpToken'], $css);
  			$css = preg_replace(self::$patterns['right'], 'left', $css);
		}
		$css = str_replace(self::$patterns['tmpToken'], 'right', $css);
		return $css;
	}
private static function fixLeftAndRight($css) {
		if (extension_loaded('mbstring')){
  			mb_internal_encoding("UTF-8");
  			mb_regex_encoding("UTF-8");
  			$css = mb_eregi_replace(trim(rtrim(self::$patterns['left'],'i'),'/'), self::$patterns['tmpToken'], $css);
  			$css = mb_eregi_replace(trim(rtrim(self::$patterns['right'],'i'),'/'), 'left', $css);
		}else{
  			$css = preg_replace(self::$patterns['left'], self::$patterns['tmpToken'], $css);
  			$css = preg_replace(self::$patterns['right'], 'left', $css);
		}
		$css = str_replace(self::$patterns['tmpToken'], 'right', $css);
		return $css;
	}
Flip rules like left: , padding-right: , etc.
@param $css string
@return string