diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 3aecdc8ccb2fa5ecd23f10ce5a10000dd4a332e4..f4d443f848a72c2a5ae99160ec6846b1b134be93 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -4,6 +4,8 @@ image: sphinxdoc/sphinx
 before_script: []
 pages:
   script:
+    - pip3 install sphinx-autoapi
+    - pip3 install nbsphinx
     - sphinx-build -M html doc public
   artifacts:
     paths:
diff --git a/doc/conf.py b/doc/conf.py
index 125f31225cab176c9c5ca9ca984814e445812ed0..9b5c60ce0c03dcf28efa337b5900be4a1132af1d 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -15,7 +15,6 @@
 import os
 import sys
 sys.path.insert(0, os.path.abspath('..'))
-import sphinx_rtd_theme
 
 # -- Project information -----------------------------------------------------
 
@@ -45,7 +44,6 @@ extensions = [
     'sphinx.ext.napoleon',
     'sphinx.ext.extlinks',
     'autoapi.extension',
-    'sphinx_rtd_theme',
     'nbsphinx'
 ]
 
@@ -98,8 +96,7 @@ pygments_style = None
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 #
-#html_theme = 'alabaster'
-html_theme = 'sphinx_rtd_theme'
+html_theme = 'classic'
 
 # 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