JSFiddle - React, Tailwind, and code Playground

by Sebastian Cubillos

HTML

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

CSS

.box {
  width: 100px;
  height: 100px;
  background: #CCC;
  line-height: 100px;
  text-align: center;
}
.box:after {
  content: "";
  width: 30px;
  height: 15px;
  background: transparent;
  border: 1px solid red;
  display: inline-block;
}