JSFiddle - React, Tailwind, and code Playground

HTML

<div class="content">
    text text text
  </div>

CSS

.content {
  width: 50%;
  height: 50px;
  border: 1px solid green;
  display: inline-block;
  z-index: 1;
}

.content::after {
  content: '';
  background: red;
  width: 100%;
  height: 100%;
  display: inline-block;
  z-index: -1;
  position: relative;
}