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HTML 

              
                <h1>Table of Contents</h1>

<div id="table-of-contents"></div>

<h2>Cat O'Nine Tails</h2>
<p>Cat o'nine tails Pieces of Eight swab carouser tackle. Pink hornswaggle gabion Sea Legs Davy Jones' Locker.</p>
<p>Hang the jib Nelsons folly trysail ahoy prow. Transom strike colors scallywag aft league.</p>

<h3 id="the-brig">The Brig</h3>
<p>Dead men tell no tales topmast Sail ho Davy Jones' Locker chantey. Wherry fluke pillage rope's end brig.</p>

<h4>Privateer</h4>
<p>Tack topgallant draft line flogging. Maroon overhaul grog blossom Privateer main sheet.</p>
<p>Provost me cackle fruit Corsair Cat o'nine tails. Hempen halter Davy Jones' Locker clipper bring a spring upon her cable run a shot across the bow.</p>

<h2>Ahoy</h2>
<p>Booty squiffy wench overhaul ahoy. Parrel Pirate Round long clothes long boat come about.</p>
<p>Squiffy jack crow's nest bilged on her anchor barkadeer. Snow bucko mizzen six pounders tack.</p>

<h3 id="man-of-war">Man-of-War</h3>
<p>Lee lad nipperkin avast pressgang. Man-of-war prow ho Sail ho landlubber or just lubber.</p>
<p>Ho no prey, no pay fire ship salmagundi capstan. Hail-shot doubloon wherry loaded to the gunwalls cutlass.</p>

<h2 id="corsair">Corsair</h2>
<p>Corsair chantey hardtack ahoy snow. Maroon cog galleon topmast tender.</p>

<h3 id="shiver-me-timbers">Shiver Me Timbers</h3>
<p>Galleon nipper Shiver me timbers lugger Nelsons folly. Wench ballast scurvy man-of-war hearties.</p>
<p>Poop deck clap of thunder Corsair grog hornswaggle. Dead men tell no tales brigantine long clothes black spot sutler.</p>

<h4 id="scurvy-dog">Scurvy Dog</h4>
<p>Jury mast Letter of Marque boatswain scurvy sheet. Jolly boat plunder jack starboard Pirate Round.</p>
<p>Holystone bring a spring upon her cable grog blossom deadlights league. Lanyard gabion reef sails booty gaff.</p>

<h4>Sea Legs</h4>
<p>Sea Legs to go on account skysail Yellow Jack heave down. Spanker heave down yawl starboard barque.</p>
<p>To go on account hulk swing the lead heave to tack. Fore fire in the hole prow run a rig Jack Ketch.</p>

<h2 id="quarterdeck">On the Quarterdeck</h2>
<p>Tack chase red ensign league pinnace. Holystone quarterdeck me boatswain rope's end.</p>
<p>Sink me lanyard Pieces of Eight starboard black spot. Blimey heave down crimp mutiny matey.</p>

<h3 id="jolly-roger">Jolly Roger</h3>
<p>Belay piracy come about jolly boat transom. Heave to gally snow Arr wherry.</p>
<p>Sutler Davy Jones' Locker ahoy walk the plank lugger. Jolly Roger matey hornswaggle Privateer marooned.</p>

<h2>Davy Jones' Locker</h2>
<p>Davy Jones' Locker jib trysail bowsprit heave down. Transom square-rigged clipper Jack Ketch chandler.</p>
<p>Square-rigged yawl execution dock sloop American Main. Six pounders red ensign lugger heave to dead men tell no tales.</p>

<h3 id="sloop">Sloop</h3>
<p>Spanker rutters Arr sloop pinnace. List crimp swab Blimey grog.</p>
<p>Shiver me timbers hulk black jack Pirate Round clap of thunder. Scuppers six pounders carouser spirits jib.</p>

<footer>
  <p>
    <small>Text provided by <a href="https://pirateipsum.me">Pirate Ipsum</a>. ☠️</small>
  </p>
</footer>
!

CSS 

              
                *, *::before {
  box-sizing: border-box;
}

:root {
  scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
  :root {
    scroll-behavior: auto;
  }
}

body {
  width: 88%;
  max-width: 34rem;
  margin: 1rem auto;
  line-height: 1.5;
  font-family: Georgia, 'Times New Roman', Times, serif;
}

:target::before {
  content: '👉 ';
}
!

JS 

              
                ;(function () {

  // Opt into strict mode
  'use strict';


  //
  // Variables
  //

  // Get the #table-of-contents element
  const tableOfContents = document.querySelector('#table-of-contents');

  // Get all h2 elements as an array
  const headings = [...document.querySelectorAll('h2')];


  //
  // Functions
  //

  /**
   * Create a skip link for a heading
   * @param {HTMLHeadingElement} heading The heading
   * @returns {String} An HTML string
   */
  function createSkipLink (heading) {
    // If the heading doesn't have an ID, create one
    if (!heading.id) {
      heading.id = heading.textContent.replace(/\s+/g, '-');
    }

    // Return the HTML string
    return `
      <li>
        <a href="#${heading.id}">
          ${heading.textContent}
        </a>
      </li>
    `;
  }

  /**
   * Render the table of contents
   */
  function render () {
    // If there aren't any headings, just bail
    if (headings.length < 1) return;

    // Build and insert the table of contents
    tableOfContents.innerHTML = `
      <ol>
        ${headings.map(createSkipLink).join('')}
      </ol>
    `;
  }


  //
  // Inits & Event Listeners
  //

  // Render the table of contents
  render();

})();
!
999px

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