JSFiddle - React, Tailwind, and code Playground

HTML

<!-- language: lang-html -->

    <div id="container">
        <div id="right">
        </div>
        <div id="left">        
        </div>
    </div>

<!-- end snippet -->

CSS

#container {
        width: 80%;
        height: 200px;
        margin: 0 auto;
        border: 1px solid grey;
    }

    #left {
        height: 100px;
        background-color: red;
    }

    #right {
        width: 100px;
        height: 100px;
        background-color: green;
        float:right
    }