JSFiddle - React, Tailwind, and code Playground

HTML

<div id="box">
    <p>Howdy.</p>
</div>
<div id="controller">
    <button id="set-bg">Change Background</button>
</div>

CSS

#box {
    background: red;
}

JavaScript

$('#set-bg').click(function() {
    $('#box').css('cssText', 'background: blue !important');
});