<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">
<body>
<div class="w3-container">
<h2>Tabs</h2>
<p>Tabs are perfect for single page web applications, or for web pages capable of displaying different subjects. Click on the links below.</p>
</div>
<div class="w3-bar w3-black">
<button class="w3-bar-item w3-button" onclick="openCity('London')">London</button>
<button class="w3-bar-item w3-button" onclick="openCity('Paris')">Paris</button>
<button class="w3-bar-item w3-button" onclick="openCity('Tokyo')">Tokyo</button>
</div>
<div id="London" class="w3-container city">
<h2>London</h2>
<p>London is the capital city of England.</p>
</div>
<div id="Paris" class="w3-container city" style="display:none">
<h2>Paris</h2>
<p>Paris is the capital of France.</p>
</div>
<div id="Tokyo" class="w3-container city" style="display:none">
<h2>Tokyo</h2>
<p>Tokyo is the capital of Japan.</p>
</div>
<script>
function openCity(cityName) {