Update 404.html according to the theme (v3.1.0)

404.html

@@ -6,9 +6,6 @@ permalink: /404.html
 redirect_from:
   - /norobots/
   - /assets/
-  - /tabs/
-  - /categories/
-  - /tags/
   - /posts/
 
 dynamic_title: true
@@ -16,5 +13,9 @@ dynamic_title: true
 
 <div class="lead">
   <p>Sorry, we've misplaced that URL or it's pointing to something that doesn't exist. </p>
-  <p><a href="{{ site.baseurl }}/">Head back Home</a> to try finding it again, or search for it on the <a href="{{ site.baseurl }}/tabs/archives">Archives page</a>.</p>
+  <p>
+    <a href="{{ '/' | relative_url }}">Head back Home</a>
+    to try finding it again, or search for it on the
+    <a href="{{ 'archives' | relative_url }}">Archives page</a>.
+  </p>
 </div>