public function classes($classes)
    {
        if (! is_array($classes)) {
            $classes = func_get_args();
        }

        $html = '';

        foreach ($classes as $name => $bool) {
            if (is_int($name)) {
                $name = $bool;
                $bool = true;
            }

            if ($bool) {
                $html .= $name.' ';
            }
        }

        if (!empty($html)) {
            return ' class="'.trim($html).'"';
        }

        return '';
    }