Bootstrap/docs/_includes/home-nav.html

<header class="navbar navbar-inverse navbar-static-top bs-docs-nav" id="top" role="banner">
  <div class="container">
    <div class="navbar-header">
      <button class="navbar-toggle collapsed" type="button" data-toggle="collapse" data-target=".bs-navbar-collapse">
        <span class="sr-only">Toggle navigation</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
      </button>
      <a href="../" class="navbar-brand">Bootstrap</a>
    </div>
    <nav class="collapse navbar-collapse bs-navbar-collapse" role="navigation">
      <ul class="nav navbar-nav">
        {% for group in site.data.nav %}
          {% assign link = group.pages | first %}
          {% assign slug = group.title | downcase | replace: ' ', '-' || page.title | downcase | replace: ' ', '-' %}
          <li class="nav-item">
            <a class="nav-link" href="{{ site.baseurl }}{{ group.title | downcase | replace: ' ', '-' }}/{{ link.title | downcase | replace: ' ', '-' || page.title | downcase | replace: ' ', '-'  }}">
              {{ group.title }}
            </a>
          </li>
        {% endfor %}
      </ul>
      <ul class="nav navbar-nav navbar-right">
        <li class="nav-item">
          <a class="nav-link" href="{{ site.expo }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Expo');">Expo</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="{{ site.blog }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Blog');">Blog</a>
        </li>
      </ul>
    </nav>
  </div>
</header>