<link href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<div class="container">
<div class="panel-group" id="accordion">
<div class="panel panel-default panel-lv1" id="panel_id_bg">
<div class="panel-heading">
<h4 class="panel-title">
<a data-toggle="collapse" data-target="#collapse_id_bg"
href="#collapse_id_bg" class="collapsed">
Identification & Background
</a>
</h4>
</div>
<div id="collapse_id_bg" class="panel-collapse collapse">
<div class="panel panel-default panel-lv2" id="panel_identity">
<div class="panel-heading">
<h4 class="panel-title">
<a data-toggle="collapse" data-target="#collapse_identity"
href="#collapse_identity" class="collapsed">
Identity
</a>
</h4>
</div>
<div id="collapse_identity" class="panel-collapse collapse">
<form class="form-horizontal">
<fieldset>
<div class="form-group">
<label class="col-md-4 control-label" for="identity_first_name">First Name</label>
<div class="col-md-4">
<input id="identity_first_name" name="identity_first_name" placeholder="first name" class="form-control input-md" required="" type="text">