public function fetch(array $options = [], array $modifyVars = [])
    {
        if (empty($options['overwrite'])) {
            $options['overwrite'] = true;
        }
        $overwrite = $options['overwrite'];
        unset($options['overwrite']);

        $matches = $css = $less = [];
        preg_match_all('@(<link[^>]+>)@', $this->_View->fetch('css'), $matches);

        if (empty($matches)) {
            return null;
        }

        $matches = array_shift($matches);

        foreach ($matches as $stylesheet) {
            if (strpos($stylesheet, 'rel="stylesheet/less"') !== false) {
                $match = [];
                preg_match('@href="([^"]+)"@', $stylesheet, $match);
                $file = rtrim(array_pop($match), '?');
                array_push($less, $this->less($file, $options, $modifyVars));
                continue;
            }
            array_push($css, $stylesheet);
        }

        if ($overwrite) {
            $this->_View->Blocks->set('css', join($css));
        }

        return join($less);
    }