Add CSS animated background from codepen to squarespace site

Site URL: https://thebutterflynest.squarespace.com/

I have been trying to add this code (https://codepen.io/thelovenest/pen/GRMyaQQ) to my site and I've tried everything. I cannot see where I'm going wrong. The idea is to only have the animation on the homepage so it looks like Butterflies are welcoming customers to my website. I've tried the <style></style> and it didn't work. If anyone could help that would be great. Thanks! 

Try adding a Code Block >> Paste this code

<p id="help">Try your mouse ^^</p>
<link rel="stylesheet" href="https://oarfish-goby-pc5y.squarespace.com/style.css" />
<style>
  canvas {
  position: fixed;
  width: 100%;
  height: 100%;
  z-index: -1;
}

#help {
  font-family: Helvetica, Arial, sans-serif;
  font-size: 10px;
  width: 100%;
  position:absolute;
  color: #555;
  text-align: center;
  z-index: 0;
}
</style>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/100/three.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.7.5/dat.gui.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/tween.js/16.7.0/Tween.js"></script>
<script src="https://klevron.github.io/codepen/three.js/OrbitControls.js"></script>
<script>
  const nbButterflies = 100;
var conf, scene, camera, cameraCtrl, light, renderer;
var whw, whh;

var butterflies;
var bodyTexture, wingTexture1, wingTexture2, wingTexture3, bodyTexture4, wingTexture4;
var destination = new THREE.Vector3();

var mouse = new THREE.Vector2();
var mouseOver = false;
var mousePlane = new THREE.Plane(new THREE.Vector3(0, 0, 1), 0);
var mousePosition = new THREE.Vector3();
var raycaster = new THREE.Raycaster();

function init() {
  conf = {
    attraction: 0.03,
    velocityLimit: 1.2,
    move: true,
    followMouse: true,
    shuffle: shuffle
  };

  scene = new THREE.Scene();
  camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 0.1, 1000);
  cameraCtrl = new THREE.OrbitControls(camera);

  renderer = new THREE.WebGLRenderer();
  renderer.setSize(window.innerWidth, window.innerHeight);
  document.body.appendChild(renderer.domElement);

  initScene();

  const gui = new dat.GUI();
  gui.add(conf, 'move');
  gui.add(conf, 'followMouse');
  gui.add(conf, 'attraction', 0.01, 0.1);
  gui.add(conf, 'velocityLimit', 0.1, 2);
  gui.add(conf, 'shuffle');
  gui.close();

  onWindowResize();
  window.addEventListener('resize', onWindowResize, false);

  document.addEventListener('mousemove', onMouseMove, false);
  // document.addEventListener('mouseover', function () { mouseOver = true; }, false);
  document.addEventListener('mouseout', function () { mouseOver = false; }, false);

  animate();
};

function initScene() {
  scene = new THREE.Scene();
  scene.background = new THREE.Color(0xffffff);

  camera.position.z = 75;

  bodyTexture = new THREE.TextureLoader().load('https://klevron.github.io/codepen/butterflies/b1.png');
  wingTexture1 = new THREE.TextureLoader().load('https://klevron.github.io/codepen/butterflies/b1w.png');
  wingTexture2 = new THREE.TextureLoader().load('https://klevron.github.io/codepen/butterflies/b2w.png');
  wingTexture3 = new THREE.TextureLoader().load('https://klevron.github.io/codepen/butterflies/b3w.png');
  bodyTexture4 = new THREE.TextureLoader().load('https://klevron.github.io/codepen/butterflies/b4.png');
  wingTexture4 = new THREE.TextureLoader().load('https://klevron.github.io/codepen/butterflies/b4w.png');

  butterflies = [];
  for (var i = 0; i < nbButterflies; i++) {
    var b = new Butterfly();
    butterflies.push(b);
    scene.add(b.o3d);
  }

  shuffle();
}

function animate() {
  requestAnimationFrame(animate);

  TWEEN.update();

  cameraCtrl.update();

  if (conf.move) {
    for (var i = 0; i < butterflies.length; i++) {
      butterflies[i].move();
    }
  }

  renderer.render(scene, camera);
};

function shuffle() {
  for (var i = 0; i < butterflies.length; i++) {
    butterflies[i].shuffle();
  }
}

function Butterfly() {
  this.minWingRotation = -Math.PI / 6;
  this.maxWingRotation = Math.PI / 2 - 0.1;
  this.wingRotation = 0;

  this.velocity = new THREE.Vector3(rnd(1, true), rnd(1, true), rnd(1, true));
  this.destination = destination;

  var confs = [
    { bodyTexture: bodyTexture, bodyW: 10, bodyH: 15, wingTexture: wingTexture1, wingW: 10, wingH: 15, wingX: 5.5 },
    { bodyTexture: bodyTexture, bodyW: 6, bodyH: 9, wingTexture: wingTexture2, wingW: 15, wingH: 20, wingX: 7.5 },
    { bodyTexture: bodyTexture, bodyW: 8, bodyH: 12, wingTexture: wingTexture3, wingW: 10, wingH: 15, wingX: 5.5 },
	{ bodyTexture: bodyTexture4, bodyW: 6, bodyH: 10, bodyY: 2, wingTexture: wingTexture4, wingW: 15, wingH: 20, wingX: 8 },
  ];

  this.init(confs[Math.floor(rnd(4))]);
}

Butterfly.prototype.init = function (bconf) {
  var geometry = new THREE.PlaneGeometry(bconf.wingW, bconf.wingH);
  var material = new THREE.MeshBasicMaterial({ transparent: true, map: bconf.wingTexture, side: THREE.DoubleSide, depthTest: false });
  var lwmesh = new THREE.Mesh(geometry, material);
  lwmesh.position.x = -bconf.wingX;
  this.lwing = new THREE.Object3D();
  this.lwing.add(lwmesh);

  var rwmesh = new THREE.Mesh(geometry, material);
  rwmesh.rotation.y = Math.PI;
  rwmesh.position.x = bconf.wingX;
  this.rwing = new THREE.Object3D();
  this.rwing.add(rwmesh);

  geometry = new THREE.PlaneGeometry(bconf.bodyW, bconf.bodyH);
  material = new THREE.MeshBasicMaterial({ transparent: true, map: bconf.bodyTexture, side: THREE.DoubleSide, depthTest: false });
  this.body = new THREE.Mesh(geometry, material);
  if (bconf.bodyY) this.body.position.y = bconf.bodyY;
  // this.body.position.z = -0.1;

  this.group = new THREE.Object3D();
  this.group.add(this.body);
  this.group.add(this.lwing);
  this.group.add(this.rwing);
  this.group.rotation.x = Math.PI / 2;
  this.group.rotation.y = Math.PI;

  this.setWingRotation(this.wingRotation);
  this.initTween();

  this.o3d = new THREE.Object3D();
  this.o3d.add(this.group);
};

Butterfly.prototype.initTween = function () {
  var duration = limit(conf.velocityLimit - this.velocity.length(), 0.1, 1.5) * 1000;
  this.wingRotation = this.minWingRotation;
  this.tweenWingRotation = new TWEEN.Tween(this)
    .to({ wingRotation: this.maxWingRotation }, duration)
    .repeat(1)
    .yoyo(true)
    // .easing(TWEEN.Easing.Cubic.InOut)
    .onComplete(function(object) {
      object.initTween();
    })
    .start();
};

Butterfly.prototype.move = function () {
  var destination;
  if (mouseOver && conf.followMouse) {
    destination = mousePosition;
  } else {
    destination = this.destination;
  }

  var dv = destination.clone().sub(this.o3d.position).normalize();
  this.velocity.x += conf.attraction * dv.x;
  this.velocity.y += conf.attraction * dv.y;
  this.velocity.z += conf.attraction * dv.z;
  this.limitVelocity();

  // update position & rotation
  this.setWingRotation(this.wingRotation);
  this.o3d.lookAt(this.o3d.position.clone().add(this.velocity));
  this.o3d.position.add(this.velocity);
};

Butterfly.prototype.limitVelocity = function (y) {
  this.velocity.x = limit(this.velocity.x, -conf.velocityLimit, conf.velocityLimit);
  this.velocity.y = limit(this.velocity.y, -conf.velocityLimit, conf.velocityLimit);
  this.velocity.z = limit(this.velocity.z, -conf.velocityLimit, conf.velocityLimit);
};

Butterfly.prototype.setWingRotation = function (y) {
  this.lwing.rotation.y = y;
  this.rwing.rotation.y = -y;
};

Butterfly.prototype.shuffle = function () {
  this.velocity = new THREE.Vector3(rnd(1, true), rnd(1, true), rnd(1, true));
  var p = new THREE.Vector3(rnd(1, true), rnd(1, true), rnd(1, true)).normalize().multiplyScalar(100);
  this.o3d.position.set(p.x, p.y, p.z);
  var scale = rnd(0.4) + 0.1;
  this.o3d.scale.set(scale, scale, scale);
}

function limit(number, min, max) {
  return Math.min(Math.max(number, min), max);
}

function rnd(max, negative) {
  return negative ? Math.random() * 2 * max - max : Math.random() * max;
}

function onWindowResize() {
  whw = window.innerWidth / 2;
  whh = window.innerHeight / 2;
  camera.aspect = window.innerWidth / window.innerHeight;
  camera.updateProjectionMatrix();
  renderer.setSize(window.innerWidth, window.innerHeight);
}

function onMouseMove(event) {
  // if (cameraCtrl.getState()!=-1) return;

  var v = new THREE.Vector3();
  camera.getWorldDirection(v);
  v.normalize();
  // console.log(v);
  mousePlane.normal = v;

  mouseOver = true;
  mouse.x = (event.clientX / window.innerWidth) * 2 - 1;
  mouse.y = - (event.clientY / window.innerHeight) * 2 + 1;

  raycaster.setFromCamera(mouse, camera);
  raycaster.ray.intersectPlane(mousePlane, mousePosition);
}

init();

</script>