JSFiddle - React, Tailwind, and code Playground

HTML

<div class="transition"></div>

CSS

div {
    width: 200px;
    height: 200px;
    border: 1px solid #333;
    margin: 20px;
}

div.transition {
    height: 100px;
    width: 100px;
    background-color: #ffffff;
    transition: background-color 1s linear;
    -moz-transition: background-color 1s linear;
    -o-transition: background-color 1s linear;
    -webkit-transition: background-color 1s linear;
}
div.animated {
    background-color: #ff0000;
}

JavaScript

$(document).ready(function() {
    
    $('.transition').addClass('animated');
    
});