JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
	<div id="header">
		<h1>
			Example
		</h1>
	</div>
	<div id="navigation">
		<ul>
			<li><a href="#">Home</a></li>
			<li><a href="#">About</a></li>
			<li><a href="#">Services</a></li>
			<li><a href="#">Contact us</a></li>
		</ul>
	</div>
</div>

CSS

#container
{
	margin: 0 auto;
	width: 350px;
	background: #fff;
    float: left;
}

#header
{
	background: #ccc;
	padding: 20px;
}

#header h1 { margin: 0; }

#navigation
{
	float: left;
	width: 350px;
	background: #333;
}

#navigation ul
{
	margin: 0;
	padding: 0;
}

#navigation ul li
{
	list-style-type: none;
	display: inline;
}

#navigation li a
{
	display: block;
	float: left;
	padding: 5px 10px;
	color: #fff;
	text-decoration: none;
	border-right: 1px solid #fff;
}

#navigation li a:hover 
{ 
    background: #383; 
}

html, body
{
    margin: 0;
    padding: 0;
}