JSFiddle - React, Tailwind, and code Playground

HTML

<div class="a">div 1</div>
<div class="b">div 2</div>
<div class="a">div 3</div>
<div class="b">div 4</div>

CSS

html, body {
   height: 100%;
}   
    
div { 
    height: 100%;
}

/* for demo purposes */

div.a {
    background-color: silver;
}

div.b {
    background-color: cyan;
}