Bootstrap Alert Box on Button Click

HTML

<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.0.4/css/bootstrap-combined.min.css">
<script src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.0.4/js/bootstrap.min.js"></script>
<div class="container">

  <div class="span4 pull-right">
    <div class="alert alert-danger fade">
      <button type="button" class="close" data-dismiss="alert">×</button>
      <strong>Alert!</strong> Here is my message..
    </div>
  </div>
</div>

JavaScript

$(".btn").on("click", function() {
    $(".alert").removeClass("in").show();
	$(".alert").delay(200).addClass("in").fadeOut(2000);
});