public function render(\DOMDocument $domDocument)
    {
        $stylesheetXml = $domDocument->createElement("stylesheet");
        if ($this->styles3d) {
            $stylesXml = $domDocument->createElement("frame3dstyles");
            $stylesheetXml->appendChild($stylesXml);
            foreach ($this->styles3d as $style3d) {
                $style3dXml = $style3d->render($domDocument);
                $stylesXml->appendChild($style3dXml);
            }
        }
        if ($this->mood) {
            $moodXml = $this->mood->render($domDocument);
            $stylesheetXml->appendChild($moodXml);
        }
        return $stylesheetXml;
    }