examples/hello_world.html

<html>
  <body>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/92/three.js"></script>
  <script>
    function init() {
      container = document.createElement('div');
      document.body.appendChild(container);

      camera = new THREE.PerspectiveCamera(30, window.innerWidth / window.innerHeight, 1, 1500);
      camera.position.set(0, 4, 7);
      camera.lookAt(new THREE.Vector3());

      fov = camera.fov;

      scene = new THREE.Scene();
      scene.background = new THREE.Color(0x3B3961);

      renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true });
      renderer.setPixelRatio(window.devicePixelRatio);
      renderer.setSize(800, 800);
      container.appendChild(renderer.domElement);
    }

    function animate() {
      renderer.state.reset();
      camera.fov = fov;
      camera.aspect = window.innerWidth / window.innerHeight;
      renderer.render(scene, camera);
      camera.updateProjectionMatrix();
      requestAnimationFrame(animate);
    }

    init();
    animate();
  </script>
  </body>
</html>