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HTML

            
                <div class="diamond"></div>

            
          
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CSS

            
              
.diamond {
  width:250px;
  height:250px;
  background:darkblue;
  margin:50px auto;
  border: 5px solid white;
  outline: 5px solid gold;
  transform:skewX(-35deg);
}

            
          
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JS

            
              
            
          
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