<!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 class="w3-container">
<h2>Toggle Show/Hide</h2>
<p>Click on the button to show/hide a paragraph.</p>
<button onclick="myFunction()" class="w3-btn">Button</button>
<p>Paragraph 1.</p>
<p id="Demo" class="w3-hide">Paragraph 2.</p>
<p>Paragraph 3.</p>
<script>
function myFunction() {
var x = document.getElementById("Demo");
if (x.className.indexOf("w3-show") == -1) {
x.className += " w3-show";
} else {
x.className = x.className.replace(" w3-show", "");
}
}
</script>
</body>
</html>