JSFiddle - React, Tailwind, and code Playground
HTML
<ul class="work">
<li>Work 1</li>
<li>Work 2</li>
<li>Work 3</li>
</ul>
<div>And</div>
<ul class="work">
<li>Work 3</li>
<li>Work 4</li>
<li>Work 5</li>
</ul>
CSS
li {
display:block;
}
.active {
background-color: #00ff00;
}
JavaScript
for (var item of document.querySelectorAll(".work li")) {
item.addEventListener("click", function (evt) {
evt.target.classList.add("active");
}, false);
}