<div class="shield__container">
  <div class="container__star"></div>
</div>
html{
  font-size: 16px;
  background-color: #1D1F20;
}
.shield__container{
  background-color: #000;
  width: 8.5rem;
  height: 8.5rem;
}
.container__star{
   width: 0;
    border-color: red blue white green;
    border-width: 3rem 3rem 3rem 3rem;
    border-style: solid;
    position: relative;
}

External CSS

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External JavaScript

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