JSFiddle - React, Tailwind, and code Playground

HTML

<nav>
    <ul>
    <li class ="heading">
        <a href="#">rando link</a>
    </li>
        <ul class ="content" style="display: none;">
            <li>blah</li>
        </ul>
    </ul>
</nav>

CSS

.active {
    background-color: green;
}

JavaScript

$(document).on('click', '.heading', function() {
    $(this).toggleClass("active");
    $(this).next("ul.content").slideToggle();
});