<div class="contentBox">
  <span class="contentBox__item">item</span>
  <span class="contentBox__item">item</span>
  <span class="contentBox__item">item</span>
</div>
.contentBox{
  height:200px;
  background:#ddd;
}
.contentBox:before{
  content:'';
  display: inline-block;
  vertical-align: middle;
  height: 100%;
}
.contentBox__item{
  background:blue;
  color:#fff;
}

External CSS

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External JavaScript

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