JSFiddle - React, Tailwind, and code Playground

HTML

<div class=container>
    <div class=block></div>
</div>

<div class=block></div>

CSS

.block {
    width: 50px;
    height: 80%;
    background-color: red;
    float: left;
}

.container {
    height: 400px;
    float: left;
}