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HTML

            
              <div class="foo"></div>
<div class="keyword foo"></div>
<div class="foo-keyword"></div>
            
          
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CSS

            
              div {  
  width:250px;
  height:250px;
  margin:20px;
  background:red;
  float:left;
}

[class*="keyword"] {
  background:green;
}
  
            
          
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Must be a valid URL.
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JS

            
              
            
          
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