<p class="small-text">Текст с классом small-text</p>
<p class="normal-text">Текст с классом normal-text</p>
<p class="big-text">Текст с классом big-text</p>
body {
  font-family: sans-serif;
}

.small-text {
  font-size: 12px;
}

.normal-text {
  font-size: 16px;
}

.big-text {
  font-size: 30px;
}

External CSS

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External JavaScript

This Pen doesn't use any external JavaScript resources.