JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>

CSS

div {
    border: 1px solid red;
    height: 22px;
    width: 22px;
}

.foo {
    height: 42px;
    width: 42px;
}

JavaScript

var $div = $('div');
$div.addClass('foo');
$div.html( $div.css('width') );