JSFiddle - React, Tailwind, and code Playground

by OscarSaharoy

CSS

.box {
  width: 100px;
  height: 100px;
  
  background-color: blue;
 
  transition: background-color 1.25s;
}

.box.purple {
  background-color: purple;
}

JavaScript

let DOM = document.createElement('div');

DOM.classList.add('box');

document.body.appendChild(DOM);

window.setTimeout(() => {
  DOM.classList.add('purple');
}, 0);