{{ menus.menu_links(items, attributes, 0) }}

{% macro menu_links(items, attributes, menu_level) %}
  {% import _self as menus %}
  {% if items %}
    {% if menu_level == 0 %}
      <ul{{ attributes.addClass('nav navbar-nav navbar-right') }}>
    {% else %}
      <ul class="dropdown-menu panel-collapse collapse">
    {% endif %}
    {% for item in items %}
      {%
        set classes = [
          item.is_expanded ? 'menu-item--expanded dropdown panel simple-dropdown',
          item.is_collapsed ? 'collapsed',
          item.in_active_trail ? 'active',
        ]
      %}
      <li{{ item.attributes.addClass(classes) }}>
        {{ link(item.title, item.url) }}
        {% if item.below %}
          {{ menus.menu_links(item.below, attributes, menu_level + 1) }}
        {% endif %}
      </li>
    {% endfor %}
    </ul>
  {% endif %}
{% endmacro %}