<body>
  <p>HTML Tutorial</p>
  <p>CSS Tutorial</p>
  <p>JavaScript Tutorial</p>
</body>
body {
    counter-reset: section;
}

p::before {
    counter-increment: section;
    content: "Phần " counter(section) ": ";
}

External CSS

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External JavaScript

This Pen doesn't use any external JavaScript resources.