JSFiddle - React, Tailwind, and code Playground
HTML
<div id="square"></div>
CSS
#square { width: 10px; height: 10px; background: blue; transition: width 1s, height 1s; position: absolute; left:200px; top:200px }
#square:hover { width: 100px; height: 100px; left :150px; top:150px}