    <main class="app-content">
      <div class="app-title">
        <div>
          <h1><i class="fa fa-envelope-o"></i> Mailbox</h1>
          <p>A Mailbox page sample</p>
        </div>
        <ul class="app-breadcrumb breadcrumb">
          <li class="breadcrumb-item"><i class="fa fa-home fa-lg"></i></li>
          <li class="breadcrumb-item"><a href="#">Mailbox</a></li>
        </ul>
      </div>
      <div class="row">
        <div class="col-md-3"><a class="mb-2 btn btn-primary btn-block" href="">Co