JSFiddle - React, Tailwind, and code Playground

by enagu

HTML

<h1>This is just a test</h1>

CSS

h1 {
  font-weight: 300;
  display: inline-block;
  padding-bottom: 5px;
  position: relative;
}
h1:before{
    content: "";
    position: absolute;
    width: 20%;
    height: 1px;
    bottom: 0;
    left: 0;
    border-bottom: 1px solid red;
}