はてなブックマーク

<details id="table-of-content" open> <summary>Table of Contents</summary> </details> <h1>Content 1</h1> <p>Lorem ipsum ...</p> <h2>Content 2</h2> <p>Lorem ipsum ...</p> <h3>Content 3</h3> <p>Lorem ipsum ...</p> <h4>Content 4</h4> <p>Lorem ipsum ...</p> <h5>Content 5</h5> <p>Lorem ipsum ...</p> <h6>Content 6</h6> <p>Lorem ipsum ...</p> document.addEventListener('DOMContentLoaded', () => { const hea