diff --git a/_static/theme/theme_overrides.css b/_static/theme/theme_overrides.css
index c8588ae0..e30c87f4 100644
--- a/_static/theme/theme_overrides.css
+++ b/_static/theme/theme_overrides.css
@@ -1,3 +1,7 @@
+.wy-side-nav-search {
+    background-color: #19191a;
+}
+
 .wy-table-responsive table td {
     white-space: normal !important;
 }
@@ -74,3 +78,29 @@
     gap: 10px;
     align-items: center;
 }
+
+/*
+ * Sphinx RTD theme compatibility layer
+ */
+
+.wy-plain-list-disc li ul,
+.rst-content .section ul li ul,
+.rst-content .toctree-wrapper ul li ul,
+article ul li ul {
+    margin-bottom: 12px;
+}
+
+.wy-menu-vertical header,
+.wy-menu-vertical p.caption {
+    color: #55a5d9;
+    font-weight: 700;
+    font-size: 85%;
+}
+
+.wy-menu-vertical a {
+    color: #d9d9d9;
+}
+
+.wy-menu-vertical li.current a {
+    color: #404040;
+}
diff --git a/conf.py b/conf.py
index 22505e98..eec1b90a 100644
--- a/conf.py
+++ b/conf.py
@@ -26,40 +26,28 @@
 html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
 html_static_path = ['_static']
 
+html_css_files = [
+   'https://media.readthedocs.org/css/sphinx_rtd_theme.css',
+   'https://media.readthedocs.org/css/readthedocs-doc-embed.css',
+   'theme/theme_overrides.css'
+]
+
 # Suppress "WARNING: unknown mimetype for ..." during EPUB builds.
 #   https://github.com/sphinx-doc/sphinx/issues/3214
 suppress_warnings = ['epub.unknown_project_files']
 
 on_rtd = os.environ.get('READTHEDOCS', None) == 'True'
-if not on_rtd:  # only import and set the theme if we're building docs locally
-   # Override default css to solve issues (e.g. width, overflows)
-   import sphinx_rtd_theme
-   html_theme = 'sphinx_rtd_theme'
-   html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
-   def setup(app):
-      app.add_css_file('theme/theme_overrides.css')
-
-   # We're running outside of readthedocs and expect the compiled version to 
-   # be a pre release
-   branch = 'pre-release'
+if not on_rtd:
+
+   # We're running outside of readthedocs and expect the compiled version to match the Git branch.
+   git_branch = os.environ.get('ZAMMAD_DOCS_GIT_BRANCH', None)
+
+   if git_branch == 'main':
+      branch = 'latest'
+   else:
+      branch = 'pre-release'
 
 else:
-   # Override default css to solve issues (e.g. width, overflows)
-   # html context breaks sphinx tabs ~
-   # html_context = {
-   #    'css_files': [
-   #       'https://media.readthedocs.org/css/sphinx_rtd_theme.css',
-   #       'https://media.readthedocs.org/css/readthedocs-doc-embed.css',
-   #       '_static/theme/theme_overrides.css',
-   #       '_static/theme/tabs.css'
-   #    ],
-   # }
-
-   html_css_files = [
-     'https://media.readthedocs.org/css/sphinx_rtd_theme.css',
-     'https://media.readthedocs.org/css/readthedocs-doc-embed.css',
-     'theme/theme_overrides.css'
-   ]
 
    # Get current version we're on for possible version warning
    rtd_version = os.environ.get('READTHEDOCS_VERSION')