<div class='div1'></div>
<div class='div2'></div>
.div1{
  width:0px;
  height:0px;
  margin:20px auto;
  border-top:50px solid yellowgreen;
  border-bottom:50px solid deeppink;
  border-left:50px solid bisque;
  border-right:50px solid chocolate;
}
.div2{
  width:0px;
  height:0px;
  margin:20px auto;
  border-bottom:50px solid deeppink;
  border-left:50px solid transparent;
  border-right:50px solid transparent;
}

External CSS

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External JavaScript

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