<div class="shadow">
  
</div>
body{padding-top:40px;}
.shadow{
  width: 30px;
  height: 30px;
  background: red;
  box-shadow: 35px 0px 0 blue,
              70px 0px 0 green,
              0px 35px 0 green,
              0 70px 0 blue,
              35px 35px 0 gray,
              70px 35px blue,
              35px 70px 0 green,
              70px 70px 0 gray;
}

External CSS

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External JavaScript

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