JSFiddle - React, Tailwind, and code Playground

HTML

<div class="class" >
    <div class="class" >
    </div>
</div>

CSS

div {height:100px;width:100px;padding:10px;background:green}
div.class > div.class:hover
{
    border-width:2px;
    border-style:inset;
    border-color:red;
}