protected function _styleElement()
    {
        $styleElementConfig = $this->gridConfig['styleElement'] ?? NULL;

        if( ! empty($styleElementConfig) )
        {
            $attributes = NULL;

            $sheet = Singleton::class('ZN\Hypertext\Sheet');
            $style = Singleton::class('ZN\Hypertext\Style');

            foreach( $styleElementConfig as $selector => $attr )
            {
                $attributes .= $sheet->selector($selector)->attr($attr)->create();
            }

            return $style->open().$attributes.$style->close();
        }

        return NULL;
    }