add author/description/keywords in the head section
diff --git a/templates/categories.html b/templates/categories.html
index 7046137..871964e 100644
--- a/templates/categories.html
+++ b/templates/categories.html
@@ -1,5 +1,5 @@
 {% extends "base.html" %}
-{% block title %}{{ SITENAME }} - Categories{% endblock %}
+{% block title %}Categories{% endblock %}
 {% block content %}
 <article>
   <div id="article_text">