restore default theme

conf.py

@@ -83,7 +83,7 @@
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 #
-html_theme = 'alabaster'
+html_theme = 'default'
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
@@ -99,17 +99,6 @@
 # Custom sidebar templates, must be a dictionary that maps document names
 # to template names.
 #
-# This is required for the alabaster theme
-# refs: http://alabaster.readthedocs.io/en/latest/installation.html#sidebars
-html_sidebars = {
-    '**': [
-        'about.html',
-        'navigation.html',
-        'relations.html',  # needs 'show_related': True theme option to display
-        'searchbox.html',
-        'donate.html',
-    ]
-}
 
 
 # -- Options for HTMLHelp output ------------------------------------------