<ol>
  <li>apple</li>
  <li>orange</li>
</ol>
li{
  counter-increment: li;
}
ol ::marker { 
  content: "#" counter(li) " ";
  font-size: 1rem; 
  color: red; 
  font-family: "Comic Sans MS", cursive, sans-serif; 
}

External CSS

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External JavaScript

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