<div id="div-1" class="col-50">
     
</div>

<div id="div-2" class="col-50">
     
</div>
.col-50{
  float: left;
  height: 200px;
  width: 50%; 
}
#div-1{
   background-color: red; 
}
#div-2{
   background-color: blue;
}

External CSS

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External JavaScript

This Pen doesn't use any external JavaScript resources.