JSFiddle - React, Tailwind, and code Playground

by DeadByElpy

HTML

<div class="box" id="test"></div>

CSS

.box {
  width: 100px;
  height: 100px;
  background: linear-gradient( #fff, #ccc );
    transition: all 3s;
    
}

.box:hover{
      background: linear-gradient( #ccc, #fff );
}

JavaScript

setTimeout(function() {
    window.test.style.background = 'green';
}, 5000);