diff --git a/docs/_static/css/custom.css b/docs/_static/css/custom.css
new file mode 100644
index 000000000..bc14758b3
--- /dev/null
+++ b/docs/_static/css/custom.css
@@ -0,0 +1,3 @@
+html {
+    --pst-font-size-base: 0.9rem;
+}
diff --git a/docs/conf.py b/docs/conf.py
index c9b2280f1..8cb3e361b 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -59,8 +59,8 @@ man_pages = [
     ),
 ]
 
-# Options for pydata theme
-html_theme = 'pydata_sphinx_theme'
+# Options for book theme
+html_theme = 'sphinx_book_theme'
 html_theme_options = {
     'collapse_navigation': True,
     "logo": {
@@ -69,3 +69,7 @@ html_theme_options = {
 }
 html_title = "beets"
 html_logo = "assets/beets_logo.png"
+html_static_path = ['_static']
+html_css_files = [
+    'css/custom.css',
+]