<div class='parent'>
  <span class='child-1'> First Element </span>
  <span class='child-2'> Second Element </span>
</div>
.parent {
  background-color:red;
}

.child-1 {
  float:left;
}
.child-2 {
  float:right;
}

/* Clear-fix*/

.parent::after {
  content:"";
  clear:both;
  display:table;
}

External CSS

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External JavaScript

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