<div class="box inner-shadow"></div> 

/* Setting up a box to add the inner shadow to */
.box {
  margin: 4rem auto;
  width: 50%;
  padding: 1rem;
  text-align: center;
  border-radius: 1rem;
}

/* CSS Inner Shadow Code */
.inner-shadow {
  width: 150px;
  height: 150px;
  box-shadow: inset gray 0px 0px 60px -12px; 
}

External CSS

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External JavaScript

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