CodePen

HTML

            
              <div class="it"></div>
<div class="it"></div>
<div class="it"></div>
<div class="it"></div>
<div class="it"></div>
<div class="it"></div>
            
          
!

CSS

            
              .it{
  display:inline-block;
  width:100px;
  height:100px;
  background:red;
  margin:4px;
}

.yellow{
  background:yellow;
}
            
          
!
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Must be a valid URL.
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JS

            
              $(".it").click(function() {
  $(".it").addClass("yellow");
  $(this).removeClass("yellow");
});
            
          
!
Must be a valid URL.
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via JS Hint
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