<div class="parent">
  <div class="child"></div>
</div>
.parent {
  width: 100px;
  height: 100px;
  padding: 30px;
  background-color: royalblue;
}

.child {
  width: 200px;
  height: 100px;
  background-color: orange;
  opacity: .5;
}

External CSS

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External JavaScript

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