JSFiddle - React, Tailwind, and code Playground

HTML

<h1>hello</h1>
<!-- just some comments below -->
<div style="position:absolute;top:0;">
<div style="width:200px;background:yellow">should animate to 200px</div>
<div style="width:100px;background:pink">start at 100px</div>
</div>

JavaScript

$('h1').css({marginLeft: '100px'}).animate({marginLeft: '+=100px'});