private static function fixLtrRtlInURL($css) {
		$css = preg_replace(self::$patterns['ltr_in_url'], self::$patterns['tmpToken'], $css);
		$css = preg_replace(self::$patterns['rtl_in_url'], 'ltr', $css);
		$css = str_replace(self::$patterns['tmpToken'], 'rtl', $css);

		return $css;
	}