menu.twig

<ul class="menu vertical" data-accordion-menu data-multi-open="false">
                        {% for item in primary_menu.get_items %}
                            <li class="{{ item.class }}">
                                <a href="{{ item.link }}">{{ item.title }}</a>
                                {% if item.get_children %}
                                    <ul class="menu vertical nested">
                                        {% for child in item.get_children %}
                                            <li class="{{ child.class }}">
                                                <a href="{{ child.link }}">{{ child.title }}</a>
                                                {% if child.get_children %}
                                                    <ul class="menu vertical nested">
                                                        {% for grandchild in child.get_children %}
                                                            <li class="{{ grandchild.class }}">
                                                                <a href="{{ grandchild.link }}">{{ grandchild.title }}</a>
                                                                {% if grandchild.get_children %}
                                                                    <ul class="menu vertical nested">
                                                                        {% for g_grandchild in grandchild.get_children %}
                                                                            <li class="{{ g_grandchild.class }}">
                                                                                <a href="{{ g_grandchild.link }}">{{ g_grandchild.title }}</a>
                                                                                {% if g_grandchild.get_children %}
                                                                                    <ul class="menu vertical nested">
                                                                                        {% for gg_grandchild in g_grandchild.get_children %}
                                                                                            <li class="{{ gg_grandchild.class }}">
                                                                                                <a href="{{ gg_grandchild.link }}">{{ gg_grandchild.title }}</a>
                                                                                            </li>
                                                                                        {% endfor %}
                                                                                    </ul>
                                                                                {% endif %}
                                                                            </li>
                                                                        {% endfor %}
                                                                    </ul>
                                                                {% endif %}
                                                            </li>
                                                        {% endfor %}
                                                    </ul>
                                                {% endif %}
                                            </li>
                                        {% endfor %}
                                    </ul>
                                {% endif %}
                            </li>
                        {% endfor %}
                    </ul>