JSFiddle - React, Tailwind, and code Playground
HTML
<div class="list">
<div class="woof">
<div class="box">
cheese
</div>
</div>
<div class="woof">
<div class="box">
cheeseburger
</div>
</div>
</div>
<div id="console"></div>
CSS
.background-blue {
background-color: blue;
}
JavaScript
$(document).ready(function () {
$('.list').find(".box").filter(function(){ return $(this).text().trim().toLowerCase() === 'cheese';}).addClass("background-blue");
});