JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="x">
    <li>Hugo</li>
    <li>Paul</li>
</ul>
<br>
<ul class="y">
    <li>Lisa</li>
    <li>Paula</li>
</ul>

CSS

.selected {
    background-color: yellow;
}

JavaScript

$('ul.x li')
.css({
    border: '1px black solid',
    color: 'blue'
}).click(function() {
    $(this).toggleClass('selected');
});