JSFiddle - React, Tailwind, and code Playground

HTML

<div class='left'>Left</div>
<div class='right'>Right</div>
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CSS

body {
    position: relative;
    float: left;
    height: 100%;
    width: 100%;
}

div {
    border: 1px solid red; 
    position: absolute; 
    bottom: 0px; 
    top: 0px;
}

.left {
    left: 0px;
    width: 200px;
}

.right {
    right: 0px;
    width: 200px;
}