JSFiddle - React, Tailwind, and code Playground

HTML

<div class="box">

</div>

CSS

.box{
    background-color: #ff0000;
	width:100px;
	height:100px;
	
}

JavaScript

$(".box").mouseenter(
  function(){
    $(this).animate({opacity:'0'},'1000')
  });
$(".box").mouseleave(
  function() {
    $(this).animate({opacity:'1'},'1000')
  });