JSFiddle - React, Tailwind, and code Playground

HTML

<canvas id="canvas"></canvas>

CSS

body {
  height: 100vh;
  width: 100vw;
}

canvas {
	display: block;
	position: absolute;
  z-index: 500;
  border: 2px solid red;
}

JavaScript

window.requestAnimFrame = (function() {
  return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame ||
    function(callback) {
      window.setTimeout(callback, 1000 / 60);
    };
})();

var ctx,
  widthCanvas,
  heightCanvas,
  leftEye,
  rightEye,
  mouse;

Eye = function(pos) {
  this.pos = {
    x: pos.x,
    y: pos.y
  };
  this.center = {
    x: pos.x,
    y: pos.y
  };
  this.translation = {
    x: (window.innerWidth / 2 - canvas.width / 2) + this.center.x,
    y: this.center.y
  };
}

Eye.prototype.draw = function() {
  ctx.beginPath();
  ctx.arc(this.pos.x, this.pos.y, 7, 0, Math.PI * 2);
  ctx.fillStyle = '#333';
  ctx.fill();

  ctx.beginPath();
  ctx.arc(this.pos.x, this.pos.y - 4, 3, 0, Math.PI * 2);
  ctx.fillStyle = '#fff';
  ctx.fill();
}

Eye.prototype.update = function() {
  var deltaX = mouse.x - this.translation.x;
  var deltaY = mouse.y - this.translation.y;
  var mag = Math.sqrt(deltaX * deltaX + deltaY * deltaY);
  var angleRad = Math.atan2(deltaY, deltaX);
  var newPosX = this.center.x + 6 * Math.cos(angleRad);
  var newPosY = this.center.y + 6 * Math.sin(angleRad);
  this.pos.x += (newPosX - this.pos.x) / 5;
  this.pos.y += (newPosY - this.pos.y) / 5;
}

var init = function() {
  var canvas = document.getElementById("canvas");
  var $canvas = $('#canvas');
  ctx = canvas.getContext('2d');
  container = $("body");
  widthCanvas = 300;
  heightCanvas = 250;

  $(window).resize(resizeCanvas);
  function resizeCanvas() {
    widthCanvas = $canvas.attr('width', $(container).width());
    heightCanvas = $canvas.attr('height', $(container).height());

  }
  resizeCanvas();
  canvas.width = widthCanvas;
  canvas.height = heightCanvas;
  leftEye = new Eye({
    x: 130,
    y: 95
  });
  rightEye = new Eye({
    x: 160,
    y: 85
  });
  mouse = {
    x: 0,
    y: 0
  };
  bindEventHandlers();
  draw();
}

var draw = function() {
 ...