JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
 </div>

CSS

.container {
    width: 250px;
    height: 250px;
    background: #FF0000;
    margin: 30px auto;
}

JavaScript

$(document).ready(function(){
    $('.container').hover(
      function() {
        $(this).stop().fadeTo(500, 0.1);
      },
      function() {
        $(this).stop().fadeTo(500,1);
      }
    )
});