JSFiddle - React, Tailwind, and code Playground

HTML

<div class="square">1</div>
	<div class="square">2</div>
	<div class="square">3</div>
	<div class="square">4</div>

CSS

* {font-family: sans-serif; margin: 0; padding: 0;}
html, body {height: 100%;}
.square { background: green; float: left; height: 50%; width: 50%;}
.touch {background: red;}

JavaScript

$(document).ready(function(){
  $('.square').bind('mouseenter', function(){
    $(this).addClass('touch');
  });
});