Disable prev and next links

docs_theme/nav.html

@@ -2,10 +2,10 @@
       <div class="navbar-inner">
         <div class="container-fluid">
           <a class="repo-link btn btn-primary btn-small" href="https://github.com/tomchristie/django-rest-framework/tree/master">GitHub</a>
-          <a class="repo-link btn btn-inverse btn-small" rel="prev" {% if next_page %}href="{{ next_page.url }}"{% endif %}>
+          <a class="repo-link btn btn-inverse btn-small {% if not next_page %}disabled{% endif %}" rel="prev" {% if next_page %}href="{{ next_page.url }}"{% endif %}>
             Next <i class="icon-arrow-right icon-white"></i>
           </a>
-          <a class="repo-link btn btn-inverse btn-small" rel="next" {% if previous_page %}href="{{ previous_page.url }}"{% endif %}>
+          <a class="repo-link btn btn-inverse btn-small {% if not previous_page %}disabled{% endif %}" rel="next" {% if previous_page %}href="{{ previous_page.url }}"{% endif %}>
             <i class="icon-arrow-left icon-white"></i> Previous
           </a>
           <a class="repo-link btn btn-inverse btn-small" href="#searchModal" data-toggle="modal"><i class="icon-search icon-white"></i> Search</a>