<div>
  <h3 class="section header">This is Header</h3>
  <p class="section paragraph">Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>
  <p class="section paragraph">Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>
</div>
body {
  font-size: 1.5rem;
}

div p {
  background-color: yellow;
}

External CSS

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External JavaScript

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