JSFiddle - React, Tailwind, and code Playground

by Neal

HTML

<div class='week-4 data'>a</div>
<div class='week-4 data'>b</div>
<div class='week-4 data'>c</div>
<div class='week-4 chart'>d</div>
<div class='week-5 data'>a</div>
<div class='week-5 data'>b</div>
<div class='week-5 data'>c</div>
<div class='week-5 chart'>d</div>

JavaScript

$('.week-4.chart')[0].style.backgroundColor = 'red';