JSFiddle - React, Tailwind, and code Playground

HTML

<div id="myid"/>

CSS

#myid {
   width: 100px;
   height: 100px;
  text-align: center;
  vertical-align: middle;
  background: gray;
  display: flex;
  align-items: center;
  justify-content: center;
} 

#myid:after {
  content: 'hello';
}