diff --git a/doc/custom_theme/main.html b/doc/custom_theme/main.html
index cc2a703e..96bb153e 100644
--- a/doc/custom_theme/main.html
+++ b/doc/custom_theme/main.html
@@ -2,7 +2,7 @@
{#
The entry point for the ReadTheDocs Theme.
-
+
Any theme customisations should override this file to redefine blocks defined in
the various templates. The custom theme should only need to define a main.html
which `{% extends "base.html" %}` and defines various blocks which will replace
@@ -14,7 +14,7 @@
-{%- if 'media.readthedocs.org' not in config.extra_css[0] %}
+{%- if config.extra_css|length and 'media.readthedocs.org' not in config.extra_css[0] %}
{%- endif %}
diff --git a/mkdocs.yml b/mkdocs.yml
index 2e201d03..46325b67 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -12,7 +12,7 @@ site_dir: doc/html
# - https://github.com/rtfd/readthedocs.org/issues/4314
# strict: true
-pages:
+nav:
- Home: index.md
- Setup:
- Server configuration: Server-configuration.md