JSFiddle - React, Tailwind, and code Playground

HTML

<div id="left"></div>
<div id="right"></div>
<div id="container">
    Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!<br />Hi!
</div>

CSS

html, body {
    margin: 0; padding: 0; border: 0; 
}
body {
    background: #ccc
}
#left, #right {
    position: fixed;
    width: 50%;
    height: 100%;
    top: 0
}
#left {
    background: #ccc;
    left: 0
}
#right {
    background: #999;
    right: 0
}
#container {
    background: #fff;
    width: 80%;
    margin: 0 auto;
    position: relative
}