JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://rawgit.com/mrdoob/three.js/r79/build/three.js"></script>
<script src="https://rawgit.com/mrdoob/three.js/r79/examples/js/controls/OrbitControls.js"></script>

JavaScript

var scene = new THREE.Scene();
var camera = new THREE.PerspectiveCamera( 75, window.innerWidth/window.innerHeight, 0.1, 1000 );
camera.position.z = 5;
camera.position.y = 5;
camera.position.x = -5;
var controls = new THREE.OrbitControls(camera);

var renderer = new THREE.WebGLRenderer({logarithmicDepthBuffer:true});
renderer.shadowMap.enabled = true;
renderer.shadowMapSoft = true;
renderer.setSize( window.innerWidth, window.innerHeight );
document.body.appendChild( renderer.domElement );		

var geometry = new THREE.BoxGeometry( 1, 1, 1 );
var material = new THREE.MeshStandardMaterial( { color: 0x00ff00 } );
var cube = new THREE.Mesh( geometry, material );
cube.castShadow = true;
cube.receiveShadow = true;
scene.add( cube );
      
var geometry2 = new THREE.BoxGeometry( 10, 0.1, 10 );
var material2 = new THREE.MeshStandardMaterial( { color: 0x00ffff } );
var cube2 = new THREE.Mesh( geometry2, material2 );
cube2.position.set(0,-0.5,0);
cube2.castShadow = true;
cube2.receiveShadow = true;
scene.add( cube2 );

var directionalLight = new THREE.DirectionalLight(0xffffff, 1);
directionalLight.position.set(10,10,10);
directionalLight.castShadow = true;
scene.add(directionalLight);

scene.add(new THREE.CameraHelper(directionalLight.shadow.camera));

			var render = function () {
				requestAnimationFrame( render );
				controls.update();
				renderer.render(scene, camera);
			};

			render();