| 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152 | <header class="navbar navbar-expand-md navbar-light fixed-top bg-light" role="navigation">  <!-- Main title -->  <a class="navbar-brand" href="{{ nav.homepage.url }}">{{ config.site_name }}</a>  <!-- Collapsed navigation -->  {% if nav|length>1 or (page.next_page or page.previous_page) or config.repo_url %}  <!-- Expander button -->  <button type="button" class="navbar-toggler" data-toggle="collapse" data-target=".navbar-collapse" aria-label="Toggle navigation">    <span class="navbar-toggler-icon"></span>  </button>  {% endif %}  <!-- Expanded navigation -->  <div class="navbar-collapse collapse">    {% if nav|length>1 %}    <!-- Main navigation -->    <ul class="navbar-nav mr-auto">      {% for nav_item in nav %}      {% if nav_item.children %}      <li class="dropdown{% if nav_item.active %} active{% endif %}">        <a href="#" class="dropdown-toggle" data-toggle="dropdown">{{ nav_item.title }} <b class="caret"></b></a>        <ul class="dropdown-menu">          {% for nav_item in nav_item.children %}          {% include "nav-sub.html" %}          {% endfor %}        </ul>      </li>      {% else %}      <li class="nav-item{% if nav_item.active %} active{% endif %}">        <a class="nav-link" href="{{ nav_item.url }}">{{ nav_item.title }}</a>      </li>      {% endif %}      {% endfor %}    </ul>    {% endif %}    <ul class="navbar-nav ml-auto">      {% if config.repo_url %}      <li class="nav-item">        <a class="nav-link" href="{{ config.repo_url }}">          {% if config.repo_name == 'GitHub' %}          <i class="fa fa-github"></i>          {% elif config.repo_name == 'Bitbucket' %}          <i class="fa fa-bitbucket"></i>          {% endif %}          {{ config.repo_name }}        </a>      </li>      {% endif %}    </ul>  </div></header>
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