JSFiddle - React, Tailwind, and code Playground

HTML

<div id="game">
  <div id="square0"></div>
  <div id="square1"></div>
  <div id="notepad"></div>
  <div id="pad"></div>
</div>

<script type="text/javascript">
  var gameWidth = 400
  var gameHeight = 400
  var intervalOne, intervalTwo, timeoutOne, x
  var angle = 2
  var tempX = 0
  var tempY = 0
  var block = 1
  var square = 0
  var squareTop = 0
  var squareLeft = 0
  var squareMotion = 1
  var speed = 80
  var getPad = 0
  var nextScore = 0
  var score = 0
  var count = 0
  var collisionOne = 0
  var collisionTwo = 0
  var collisionThree = 0

  document.body.style.margin = "0px"
  document.body.style.padding = "0px"

  function setupGame() {
    document.getElementById("game").style.borderRight = "1px solid #aaa"
    document.getElementById("game").style.borderRight = "1px solid #aaa"
    document.getElementById("game").style.borderBottom = "1px solid #aaa"
    document.getElementById("game").style.width = gameWidth + "px"
    document.getElementById("game").style.height = gameHeight + "px"
    document.getElementById("square0").style.position = "absolute"
    document.getElementById("square0").style.width = "40px"
    document.getElementById("square0").style.height = "40px"
    document.getElementById("square0").style.backgroundColor = "#444"
    document.getElementById("square0").style.display = "none"
    document.getElementById("square1").style.position = "absolute"
    document.getElementById("square1").style.width = "40px"
    document.getElementById("square1").style.height = "40px"
    document.getElementById("square1").style.backgroundColor = "#444"
    document.getElementById("square1").style.display = "none"
    document.getElementById("pad").style.position = "absolute"
    document.getElementById("pad").style.width = "60px"
    document.getElementById("pad").style.height = "30px"
    document.getElementById("pad").style.paddingTop = "10px"
    document.getElementById("pad").style.textAlign = "center"
    document.getElementById("pad").style.font =...