JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li>
        Item 1
        <ul>
            <li>Item 1.1</li>
            <li>Item 1.2</li>
        </ul>
    </li>
    <li>
        Item 2
    </li>
</ul>

CSS

li.has-ul { background-color: red }

JavaScript

$('li').has('ul').addClass('has-ul');