diff --git a/docs/_config.yml b/docs/_config.yml
index 7041cbc4..53ae4de9 100644
--- a/docs/_config.yml
+++ b/docs/_config.yml
@@ -3,7 +3,7 @@
 
 title: DemesDraw
 author: Graham Gower
-copyright: "2021"
+copyright: "2021-2023"
 only_build_toc_files: true
 
 execute:
@@ -15,11 +15,6 @@ repository:
   path_to_book: docs
   branch: main
 
-html:
-  use_issues_button: true
-  use_repository_button: true
-  use_edit_page_button: true
-
 sphinx:
   extra_extensions:
   - sphinx.ext.autodoc
@@ -30,7 +25,8 @@ sphinx:
 
   local_extensions:
     # Add version string to the navbar and footer.
-    inject_version: _ext
+    # Works with sphinx-book-theme, but not with piccolo_theme.
+    #inject_version: _ext
 
   config:
     autodoc_typehints: description
@@ -39,3 +35,19 @@ sphinx:
       demes: ["https://popsim-consortium.github.io/demes-docs/stable/", null]
       matplotlib: ["https://matplotlib.org/stable/", null]
     issues_github_path: grahamgower/demesdraw
+
+    html_show_sphinx: false
+    # https://piccolo-theme.readthedocs.io/
+    html_theme: "piccolo_theme"
+    # some custom css to fix piccolo/notebook in dark modes
+    html_static_path: ["_static"]
+    html_css_files: ["custom.css"]
+
+    html_theme_options:
+        globaltoc_collapse: false
+        globaltoc_maxdepth: -1
+        globaltoc_includehidden: true
+
+        ## piccolo_theme options
+        #dark_mode_code_blocks: false
+        source_url: https://github.com/grahamgower/demesdraw
diff --git a/docs/_static/custom.css b/docs/_static/custom.css
new file mode 100644
index 00000000..74548174
--- /dev/null
+++ b/docs/_static/custom.css
@@ -0,0 +1,26 @@
+/*
+ * Fixes for images with transparent backgrounds and notebook output
+ * when using dark mode with piccolo_theme.
+ */
+.cell_output img {
+    background-color: white !important;
+}
+section img {
+    background-color: white !important;
+}
+div.cell summary {
+    background-color: #eeffcc !important;
+    color: #252630 !important;
+}
+div.cell_output,
+div.cell_input
+{
+    background: inherit !important;
+}
+
+.cell_output .output.text_plain,
+.cell_output .output.traceback,
+.cell_output .output.stream,
+.cell_output .output.stderr {
+    background: inherit !important;
+}
diff --git a/requirements/docs.txt b/requirements/docs.txt
index 373c8fe1..c2dff8be 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -1,3 +1,4 @@
-jupyter-book==0.13.2
+jupyter-book==0.15.1
+piccolo_theme==0.15.0
 sphinx-issues==3.0.1
 sphinxcontrib-programoutput==0.17