index.html

<!DOCTYPE html>
<html>
	<head>
		<meta charset=utf-8 />
		<title></title>
		<link rel="stylesheet" href="dat.css">
		<script src="dat.js" type="text/javascript"></script>
		<script>
			$(document).ready(function(e){
				$('button').on('click', function(e){
					$('#' + $('#' + e.target.id).data('target')).activate();
				});
			});
		</script>
	</head>
	<body>
		<div style="position: fixed; top: 0; left: 0; z-index:20;">
			<button data-target="first" id="btn1">1 panel</button>
			<button data-target="second" id="btn2">2 panel</button>
		</div>
		<div id="viewport">

			<div class="panel fade active" id="first" style="background-color:orange">
				<p>Panel 1</p>
				<form id="form">
					<input type="text" value="you" name="who?">
					<input type="text" value="me" name="who else?" disabled>
					<button>Click me</button>
				</form>
			</div>
			<div class="panel fade" id="second" style="background-color:violet">
				<p>Panel 2</p>
			</div>
		</div>
	</body>
</html>