{% macro header_nav_link(nav_item, root) %}
  {% set root = root or nav_item %}
  {% if nav_item.children %}
    {{ header_nav_link(nav_item.children | first, root) }}
  {% else %}
    <a href="{{ nav_item.url | url }}" class="psi-header-nav__link{% if root.active %} psi-header-nav__link--active{% endif %}">
      {{ root.title }}
    </a>
  {% endif %}
{% endmacro %}

{% set class = "md-header" %}
{% if "navigation.tabs.sticky" in features %}
  {% set class = class ~ " md-header--shadow md-header--lifted" %}
{% elif "navigation.tabs" not in features %}
  {% set class = class ~ " md-header--shadow" %}
{% endif %}
<header class="{{ class }}" data-md-component="header">
  <nav class="md-header__inner md-grid" aria-label="{{ lang.t('header') }}">
    <a href="{{ config.extra.homepage | d(nav.homepage.url, true) | url }}" title="{{ config.site_name | e }}" class="md-header__button md-logo" aria-label="{{ config.site_name }}" data-md-component="logo">
      {% include "partials/logo.html" %}
    </a>
    <label class="md-header__button md-icon" for="__drawer">
      {% set icon = config.theme.icon.menu or "material/menu" %}
      {% include ".icons/" ~ icon ~ ".svg" %}
    </label>
    <div class="md-header__title" data-md-component="header-title">
      <div class="md-header__ellipsis">
        <div class="md-header__topic">
          <span class="md-ellipsis">
            {{ config.site_name }}
          </span>
        </div>
        <div class="md-header__topic" data-md-component="header-topic">
          <span class="md-ellipsis">
            {% if page.meta and page.meta.title %}
              {{ page.meta.title }}
            {% else %}
              {{ page.title }}
            {% endif %}
          </span>
        </div>
      </div>
    </div>
    <div class="psi-header-nav" aria-label="Primary navigation">
      {% for nav_item in nav.items %}
        {{ header_nav_link(nav_item) }}
      {% endfor %}
    </div>
    {% if config.theme.palette %}
      {% if not config.theme.palette is mapping %}
        {% include "partials/palette.html" %}
      {% endif %}
    {% endif %}
    {% if not config.theme.palette is mapping %}
      {% include "partials/javascripts/palette.html" %}
    {% endif %}
    {% if config.extra.alternate %}
      {% include "partials/alternate.html" %}
    {% endif %}
    {% if "material/search" in config.plugins %}
      {% set search = config.plugins["material/search"] | attr("config") %}
      {% if search.enabled %}
        <label class="md-header__button md-icon" for="__search">
          {% set icon = config.theme.icon.search or "material/magnify" %}
          {% include ".icons/" ~ icon ~ ".svg" %}
        </label>
        {% include "partials/search.html" %}
      {% endif %}
    {% endif %}
    {% if config.repo_url %}
      <div class="md-header__source">
        {% include "partials/source.html" %}
      </div>
    {% endif %}
  </nav>
  {% if "navigation.tabs.sticky" in features %}
    {% if "navigation.tabs" in features %}
      {% include "partials/tabs.html" %}
    {% endif %}
  {% endif %}
</header>