<div>
  <p>child</p>
</div>
div {
  width: 300px;
  background-color: lightblue;
}

p {
  width: 100px;
  height: 100px;
  color: #fff;
  background-color: royalblue;
  font-size: 2rem;
  text-align: center;
  line-height: 100px;
  margin: 20px;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.