switch to single-page layout

_includes/navigation.html

@@ -1,15 +1,11 @@
 <nav>
-  <!--
-  <a href="/"
-     {% if page.url == "/" %}style="color: red;"{% endif %}
-     >Hauptseite</a>
-  <a href="/about.html"
-     {% if page.url == "/about.html" %}style="color: red;"{% endif %}
-     >Über uns</a>
-  -->
-  {% for item in site.data.navigation %}
-  <a href="{{ item.link }}"
-     {% if page.url == item.link %}class="current-site"{% endif %}
-     >{{ item.name }}</a>
-  {% endfor %}
+  <!-- Gösta Hellner, Ostraka aus dem Kerameikos, Deutsches Archäologisches Institut Athen, 1963 -->
+  <ul>
+    <li class="p-intro"><a href="#intro">{{intro-page.title}}</a></li>
+    {% for node in site.posts %}
+    {% capture id %}{{ node.id | remove:'/' | downcase }}{% endcapture %}
+    <li class="p-{{id}}"><a href="#{{id}}">{{node.title}}</a></li>
+    {% endfor %}
+    <li class="p-about"><a href="#about">{{about-page.title}}</a></li>
+  </ul>
 </nav>