<!DOCTYPE html>
<html>
<title>W3.JS</title>
<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">
<script src="https://www.w3schools.com/lib/w3.js"></script>
<body class="w3-container">
<h2>Testing W3.JS with CSS</h2>
<p>Click the button to toggle h2 elements.</p>
<p>
<button class="w3-btn w3-red" onclick="w3.toggleShow('h2')">Toggle Hide/Show</button>
</p>
<div id="London" class="w3-panel w3-red city">
<h2>London</h2>
<p>London is the capital city of England.</p>
</div>
<div id="Paris" class="w3-panel w3-red city">
<h2>Paris</h2>
<p>Paris is the capital of France.</p>
</div>
<div id="Tokyo" class="w3-panel w3-red city">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan.</p>
</div>
</body>
</html>