JSFiddle - React, Tailwind, and code Playground

by Elizabeth Meyer

HTML

<header>Some nav stuff here</header>
<h1>This is the heading</h1>
<div id="theCalcDiv">This blocks needs to have a CSS calc() height of 100% - the height of the other elements.</div>

CSS

body {background: blue; height:100%;}
header {background: red; height: 20px; width:100%}
h1 {font-size:1.2em; margin:0; padding:0; height: 30px; font-weight: bold; background:yellow}
#theCalcDiv {background:green; height: calc(100% - (20px + 30px)); display:block}