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

<div class="viewport">

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

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

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

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

*, *:before, *:after {
    box-sizing: border-box;
}

.spacer {
  width: 100%;
  height: 400vh;
  display: block;
}

.viewport {
  width: 100vw;
  height: 100vh;
  display: block;
  position: fixed;
  top: 0;
  left: 0;
}

// Screen rotate and scale
// ------------------------------------ /

// Set piece screen - wrapper
.set-piece-wrapper {
	width: 236px;
	height: 334px;
  display: block;
	margin: 0 auto;
  position: absolute;
  left: 50%;
  bottom: 270px;
  z-index: 10;
}

// Set piece which rotates
.set-rotate {
	position: absolute;
	left: 0;
	top: 0;
	width: 100%;
	height: 100%;
	z-index: 1;
	background-color: #d0e1e9;
  border-radius: 10px
}

// Set piece which scales in
.set-screen {
    background-color: #b9d2d5;
    display: block;
    position: absolute;
    left: 50%;
    top: 65px;
    width: 300px;
    height: 204px;
    margin-left: -150px;
    border-radius: 6px;
    transform: scale(1);
    z-index: 2;
}