<h2>HTML</h2>
<h2>CSS</h2>
<h2>JavaScript</h2>
<h2>Python</h2>
<h2>SQL</h2>
body {
  counter-reset: section;
}

h2::before {
  counter-increment: section;
  content: "Section " counter(section) ": ";
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.