JSFiddle - React, Tailwind, and code Playground

HTML

<div></div>
<div></div>
<div></div>

CSS

* {
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
}

html, body {
    height: 100%;
}

div:nth-of-type(1) {
    background: #f00;
    height: 20%;
    border-bottom: 5px solid #f0f;
}

div:nth-of-type(2) {
    background: #00f;
    height: 70%;
}

div:nth-of-type(3) {
    background: #0f0;
    height: 10%;
}