Bootstrap 3.0 - Collapsable Panels

HTML

<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="//netdna.bootstrapcdn.com/font-awesome/3.2.1/css/font-awesome.min.css">
<div class="panel-group" id="accordion">
  <div class="panel panel-default" id="panel1">
    <div class="panel-heading">
      <h4 class="panel-title">
        <a data-toggle="collapse" data-target="#collapseOne" 
           href="#collapseOne">
          Collapsible Group Item #1
        </a>
      </h4>

    </div>
    <div id="collapseOne" class="panel-collapse collapse in">
      <div class="panel-body">
        <ul class="list-group">
          <li class="list-group-item">First item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Second item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Third item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">First item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Second item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Third item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">First item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Second item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Third item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">First item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Second item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Third item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">First item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Second item<i class="pull-right">Delete</i></li>
          <li class="list-group-item">Third item<i...

CSS

.panel-heading a:after {
  font-family: 'Glyphicons Halflings';
  content: "\e114";
  float: right;
  color: grey;
}

.panel-heading a.collapsed:after {
  content: "\e080";
}