<nav>: ナビゲーションセクション要素

<nav class="crumbs">
  <ol>
    <li class="crumb"><a href="#">Bikes</a></li>
    <li class="crumb"><a href="#">BMX</a></li>
    <li class="crumb">Jump Bike 3000</li>
  </ol>
</nav>
<h1>Jump Bike 3000</h1>
<p>
  This BMX bike is a solid step into the pro world. It looks as legit as it
  rides and is built to polish your skills.
</p>

nav {
  border-bottom: 1px solid black;
}
.crumbs ol {
  list-style-type: none;
  padding-left: 0;
}
.crumb {
  display: inline-block;
}
.crumb a::after {
  display: inline-block;
  color: #000;
  content: ">";
  font-size: 80%;
  font-weight: bold;
  padding: 0 3px;
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<nav class="menu">
  <ul>
    <li><a href="#">Home</a></li>
    <li><a href="#">About</a></li>
    <li><a href="#">Contact</a></li>
  </ul>
</nav>

<nav>
  <h2>Navigation</h2>
  <p>
    You are on my home page. To the north lies <a href="/blog">my blog</a>, from
    whence the sounds of battle can be heard. To the east you can see a large
    mountain, upon which many <a href="/school">school papers</a> are littered.
    Far up this mountain you can spy a little figure who appears to be me,
    desperately scribbling a <a href="/school/thesis">thesis</a>.
  </p>
  <p>
    To the west are several exits. One fun-looking exit is labeled
    <a href="https://games.example.com/">"games"</a>. Another more
    boring-looking exit is labeled <a href="https://isp.example.net/">ISP™</a>.
  </p>
  <p>
    To the south lies a dark and dank <a href="/about">contacts page</a>.
    Cobwebs cover its disused entrance, and at one point you see a rat run
    quickly out of the page.
  </p>
</nav>