liquid-nav.html

<nav>
	<ul>
		<li class="c-nav_logo">
			<a href="/"><img src="/img/logo-lrg.svg" alt="logo" /></a>
		</li>
		{% for nav in site.data.navigation %}
	    {% if nav.children != null %}
	      <li class="c-nav_dropdown-trigger">
	      	<a href="{{ nav.href }}">{{ nav.title }}</a>
	        <ul class="c-nav_dropdown">
	        {% for child in nav.children %}
						<li>
	          	<a href="{{ child.child_href }}">
	          		{{ child.child_title }}
	          		<span>{{ child.child_desc }}</span>
	          	</a>
	          </li>
	        {% endfor %}
	        </ul>
	     	{% else %}
	      <li>
	      	<a href="{{ nav.href }}">{{ nav.title }}</a>
	    {% endif %}
	    </li>
	  {% endfor %}
   </ul>
</nav>

navigation.yml

# Link structure for the navigation
- title: Link Name
  href: /link-url/
  children:
    - child_title: Child Link Name
      child_href: /link-url/child-link/
      child_desc: Desc micro copy line
    - child_title: Child Link Name
      child_href: /link-url/child-link/
      child_desc: Desc micro copy line
- title: Link Name
  href: /link-url/
  children:
    - child_title: Child Link Name
      child_href: /link-url/child-link/
      child_desc: Desc micro copy line
    - child_title: Child Link Name
      child_href: /link-url/child-link/
      child_desc: Desc micro copy line
- title: Link Name
  href: /link-url/
  children:
    - child_title: Child Link Name
      child_href: /link-url/child-link/
      child_desc: Desc micro copy line
    - child_title: Child Link Name
      child_href: /link-url/child-link/
      child_desc: Desc micro copy line