JSFiddle - React, Tailwind, and code Playground

HTML

<div id='cover'> Cover </div>

CSS

#cover{
  width: 200px;
  height: 200px;
  background-color: green;
}

JavaScript

var cover = document.getElementById("cover");
var cover_height = cover.clientHeight;    

cover.style.paddingTop = cover_height / 5 + "px";