JSFiddle - React, Tailwind, and code Playground

HTML

<h1>Test Test Test Test Test ........</h1>
<div></div>
<hr>

CSS

h1 {
    border-bottom: 1px solid red;
    width: 50%;
}
div {
    background-color: green;
    width: 45%;
    height:1px;
}
hr {
    width: 20%;
}