JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li>Hallo</li>
    <li>Night</li>
</ul>

CSS

ul li {
    display: inline-block;
    width: 120px;
    border-bottom: 2px solid red;
    text-align: center;
    margin-right: -5px;
}
ul li:hover {
    border-bottom: 2px solid yellow;
}