mail/src/tpl/desktop.html

<div class="nav-container nav-effect" ng-class="{'nav-menu-open': navOpen}">

  <!-- main navigation -->
  <nav class="nav-menu nav-effect" ng-include="'tpl/navigation.html'"></nav>

  <!-- content wrapper pushed right -->
  <div class="nav-pusher" ng-click="closeNav()">
    <section class="content main-content">

      <!-- left column: containing list view and navigation header -->
      <div class="column view-mail-list" ng-include="'tpl/mail-list.html'" ng-controller="MailListCtrl"></div>

      <div class="column" ng-include="'tpl/read.html'"></div>

    </section>
  </div><!--/.nav-pusher-->

</div><!--/.nav-container-->

<!-- lightbox  -->
<div class="lightbox-overlay">
  <div class="lightbox lightbox-effect">
    <div class="lightbox-body">
      <header>
        <!-- add lightbox title -->
        <h2>New email</h2>
        <button class="close" data-action="lightbox-close">&#xe007;</button>
      </header>
      <div class="content">
        <!-- add lightbox content here -->
        some content
      </div>
    </div>
  </div>
</div><!--/.lightbox-->