This is the code 

.float-wrapper::after {
  content: "";
  clear: both;
  display: block;
}
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Explanation:

.float-wrapper -> is some parent element that wraps the floating items

example:
<div class='float-wrapper'>
     <div class='floating-item'> </div>
     <div class='floating-item'> </div> 
     ....
 </div>

::after  adds  an element after the .float-wrapper, that 
has no content and clears floats from the both sides, making sure, 
other sections are not affected by floats