JSFiddle - React, Tailwind, and code Playground

HTML

<div class='parentDiv'>
    <div class='childDiv'></div>

CSS

.parentDiv {
        margin-top: 200px;
        width: 700px;
        height: 800px;
        background-color: red;
        }

    .childDiv {
        background-color: green;
        width: 50px;
        height: 50px;
        margin-top: 90px;
    }