<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.3/css/font-awesome.min.css" rel="stylesheet">
<section class="py-5 bg-danger">
<div class="container">
<div class="row">
<div class="col-md-12">
<div id="accordion">
<div class="card">
<div class="card-header bg-dark ">
<a class="card-link text-white" data-toggle="collapse" href="#collapseOne"><span class="float-right"><i class="fa fa-arrow-down"></i></span>
<h6>Collapsible Group Item #1</h6>
</a>
</div>
<div id="collapseOne" class="collapse show" data-parent="#accordion">
<div class="card-body">
Lorem ipsum..
</div>
</div>
</div>
<div class="card">
<div class="card-header bg-dark">
<a class="collapsed card-link text-white" data-toggle="collapse" href="#collapseTwo"><span class="float-right"><i class="fa fa-arrow-down"></i></span>
<h6>Collapsible Group Item #2</h6>
</a>
</div>
<div id="collapseTwo" class="collapse" data-parent="#accordion">
<div class="card-body">
Lorem ipsum..
</div>