{% if nav_item.children %}
    <li class="toctree-l1 {% if nav_item.active%}current{%endif%}">
    <a class="{% if nav_item.active%}current{%endif%}" href="{{ nav_item.children[0].url }}">{{ nav_item.title }}</a>
    <ul class="subnav">
        {% if nav_item.active %}
            {% for nav_item in nav_item.children[1:] %}
                {% include 'toc.html' %}
            {% endfor %}
        {% endif %}
    </ul>
{% else %}
    <li class="toctree-l1 {% if nav_item.active%}current{%endif%}">
    <a class="{% if nav_item.active%}current{%endif%}" href="{{ nav_item.url }}">{{ nav_item.title }}</a>
        {% if nav_item == current_page %}
            <ul class="subnav">
            {% for toc_item in toc %}
                <li class="toctree-l3"><a href="{{ toc_item.url }}">{{ toc_item.title }}</a></li>
            {% endfor %}
            </ul>
        {% endif %}
    </li>
{% endif %}