JSFiddle - React, Tailwind, and code Playground

HTML

<div class="brick small"></div>

CSS

.brick
  {
      background: red;
    position: absolute;
    transition: all 0.4s ease-in-out;
  }
  .large
  {
    width: 200px;
    height: 200px;
  }
  .small
  {
    width: 400px;
    height: 400px;
  }

JavaScript

$('.brick').removeClass('small').addClass('large');

var brick = $('<div />', {'class':'brick large', style:'transition:none; left: 9999px;'}).appendTo('body');

var h = brick.height()
var w = brick.width();
    
console.log(h)
console.log(w)