JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
    <div class="red">Red</div>
    <div class="green">green</div>
    <div class="blue">blue</div>
</div>

CSS

.container{border: 2px solid black; padding: 5px; position: relative; margin:0px; width: 100%;}

.container div {height: 20px; display: inline-block; padding:0px; margin:0px;}

.red{border: 2px solid red; width:31%; }

.green{border: 2px solid green;width:31%;}

.blue{border: 2px solid blue;width:31%;}