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<span id="trigger-office"></span>
<span class="spacer"></span>

<div class="viewport">

  <div class="set-piece-wrapper">

    <div class="set-piece set-rotate"></div>
    <!-- / This background rotates into position / -->

    <div class="set-piece set-screen"></div>
    <!-- / This background scales up from small to big / -->
  </div>
  <!-- .set-piece-wrapper -->

  <div class="floor"></div>
  <!-- .floor -->

  <span class="fred"></span>
  <!-- .fred -->


</div>
<!-- viewport -->