JSFiddle - React, Tailwind, and code Playground

by George Batt

HTML

<div class="a"></div>

CSS

.a {
    background-color: cyan;
    height: 300px;
    width: 200px;
    margin-left: 50px;
}

.a:before {    
    /* This is the one that I change */
    content: "";
    display:block;
    margin-left: -10px;
    background-color: red;
    height: 10px;
    width: 10px;
}