<div  class="test">
  
</div>
.test {
  background:conic-gradient(from 0deg,
   #f00,#f0f,#00f,#0ff,#0f0,#ff0,#f00);
  width: 300px;
  height: 300px;
  border-radius: 50%;
}

External CSS

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External JavaScript

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