<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="/lib/w3.css">
<body>
<nav class="w3-sidenav w3-light-grey w3-border" style="width:25%">
<a href="#">Link 1</a>
<a href="#">Link 2</a>
<a href="#">Link 3</a>
<a href="#">Link 4</a>
<a href="#">Link 5</a>
</nav>
<div style="margin-left:25%">
<header class="w3-container w3-dark-grey">
<h1>My Header</h1>
</header>
<div class="w3-container">
<p>Use the w3-border class to add borders around the side navigation.</p>
</div>
</div>
</body>
</html>