JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <div id="a"></div>
    <div id="b"></div>
    <div id="c"></div>
</div>

CSS

#container {
    width: 400px;
    border: 2px solid #CCCCCC;
}

#container div {
    width: 100%;
    display: inline-block;
    height: 200px;
}

#a {
    background-color: #FF0000;
}

#b {
    background-color: #00FF00;
}

#c {
    background-color: #0000FF;
}