public function close()
    {
        $html = implode('', $this->footer);
        foreach ($this->hidden as $key => $value) {
            $html .= "\n\t".$this->input('hidden', array(
                'name' => $key,
                'value' => htmlspecialchars((string) $value),
            ));
        }

        return $html."\n</form>";
    }