<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,
.container__star::before,
.container__star::after{
    width: 0;
    border-color: transparent transparent #fff transparent;
    border-width: 0 4rem 2.5rem 4rem;
    border-style: solid;
    position: absolute;
    transform: rotate(180deg);
    margin-top: 2.75rem;
    margin-left: 0.25rem;    
}

.container__star::before{
    content: '';
    margin-top: -0.15rem;
	  margin-left: -4.3rem;
    transform: rotate(70deg);
}

.container__star::after{
    content: '';
    margin-top: -0.29rem;
	  margin-left: -3.87rem;
    transform: rotate(-70deg);
}

External CSS

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External JavaScript

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