);
      document.querySelector('header').appendChild(app.xrButton.domElement);

      app.scene.addNode(new Gltf2Node({url: '../media/gltf/space/space.gltf'}));
      app.scene.addNode(new SkyboxNode({url: '../media/textures/milky-way-4k.png'}));

      // Start the XR application.
      app.run();
    </script>
  </body>
</html>
