<link href="//netdna.bootstrapcdn.com/bootstrap/3.1.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.1.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div class="container">
<div class="row">
<h2>prova</h2>
<button type="button" class="btn btn-success">Prova BOTTONE</button>
</div>
</div>