<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.7.5/js/bootstrap-select.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.7.5/css/bootstrap-select.min.css">
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Strait">
<div class="container" style="font-family: 'Strait', sans-serif;">
<div class="row">
<h1>Bootstrap 3 Select demo</h1>
<select class="selectpicker" data-style="btn-primary btn-lg btn-block" multiple data-max-options="2">
<option>PHP</option>
<option>CSS</option>
<option>HTML</option>
<option>CSS 3</option>
<option>Bootstrap</option>
<option>JavaScript</option>
</select>
<br><br><br>
<a class="btn btn-success" target="_blank" href="https://www.jquery-az.com/bootstrap-select-5-beautiful-styles/">reference code</a>
</div>
</div>
