bananasite/_includes/header.html

<header class="site-header">
  {%- assign default_paths = site.pages | sort:"order" | map: "path" -%}
  {%- assign page_paths = site.header_pages | default: default_paths -%}
  {%- assign titles_size = site.pages | map: 'title' | join: '' | size -%}
  <a class="site-title" rel="author" href="{{ "/" | relative_url }}">{{ site.title | escape }}</a>

  {%- if titles_size > 0 -%}
    <nav class="site-nav">
      <input type="checkbox" id="nav-trigger" class="nav-trigger" />
      <label for="nav-trigger">
        <span class="menu-icon">
          <svg viewBox="0 0 18 15" width="18px" height="15px">
            <path d="M18,1.484c0,0.82-0.665,1.484-1.484,1.484H1.484C0.665,2.969,0,2.304,0,1.484l0,0C0,0.665,0.665,0,1.484,0 h15.032C17.335,0,18,0.665,18,1.484L18,1.484z M18,7.516C18,8.335,17.335,9,16.516,9H1.484C0.665,9,0,8.335,0,7.516l0,0 c0-0.82,0.665-1.484,1.484-1.484h15.032C17.335,6.031,18,6.696,18,7.516L18,7.516z M18,13.516C18,14.335,17.335,15,16.516,15H1.484 C0.665,15,0,14.335,0,13.516l0,0c0-0.82,0.665-1.483,1.484-1.483h15.032C17.335,12.031,18,12.695,18,13.516L18,13.516z"/>
          </svg>
        </span>
      </label>

      <div class="trigger">
        {%- for path in page_paths -%}
          {%- assign my_page = site.pages | where: "path", path | first -%}
          {%- if my_page.title -%}
            {% if my_page.url == page.url %}
              {% assign className = "page-link active" %}
            {% else %}
              {% assign className = "page-link" %}
            {% endif %}
            <a class="{{ className }}" href="{{ my_page.url | relative_url }}">
              {{ my_page.title | escape }}
            </a>
          {%- endif -%}
        {%- endfor -%}
      </div>
    </nav>
  {%- endif -%}


  <div class="site-icon">
    <img src="{{ site.iconURL }}" />
  </div>

</header>