JSFiddle - React, Tailwind, and code Playground

HTML

<div id="top">
	<div id="settings">
    </div>
    <div id="menu">
    </div>
</div>
<div id="body-content">
</div>

CSS

#settings{
		width:100%;
		background:#383838;
		height:60px;
	}
	#menu{
		width:100%;
		position:relative;
		height:100px;
		background:#aaa;
	}
	#body-content{
		height:900px;
		position:relative;
	}