<div class="row">
  <div class="col-4">
    <div class="box"></div>
  </div>
  
  <div class="col-4">
    <div class="box"></div>
  </div>
  
  <div class="col-7">
    <div class="box"></div>
  </div>
</div>  
.box {
  width: 100%;
  height: 100px;
  margin: 10px;
  background: blue;
}

External CSS

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External JavaScript

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