JSFiddle - React, Tailwind, and code Playground

HTML

<body>

    <div id="header">

        <h1>My test site</h1> 
    </div>

    <div id="navbar">
    </div>

    <div id="main_window">
    </div>


</body>

CSS

html {
    padding: 0;
}

body {
    margin: 0%;
    padding: 0%;
    font-family: sans-serif;
}

#header {
    background-color: black;
    height: 150px;
    margin: 0px;
    color: white;
}

#header, h1 {
/*position: absolute;*/
bottom: 0;
margin:0px;
}

#navbar {
    background-color: darkblue;;
    height: 40px;
    box-shadow: 0px 10px 8px #888888;
}