JSFiddle - React, Tailwind, and code Playground

HTML

<div id="wrapper">
        <div id="header"> </div>
        <div id="right"> </div>
        <div id="left"> </div>
        <div id="footer"> </div>
    </div>

CSS

#wrapper {
        width:80%;
        margin: auto;
    }
    #header {
        background-color: black;
        height: 60px;
    }
    #left {
        background-color: blue;
        width: 20%;
        float: left;
    }
    #right {
        background-color: green;
        width: 80%;
        float: right;
    }
    #left, #right {
        height: 600px;
    }
    #footer {
        background-color: red;
        height: 40px;
        clear: both;
    }
    #left, #right, #header, #footer {
        margin: 0;
        padding: 0;
        border-radius: 5px;
    }