diff --git a/pyproject.toml b/pyproject.toml
index a2eedae57e9b2dbc06868d5cdbda06c51c3e21ee..48795fa3ab5b83ba7bd54b191a2531c00031ddeb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -33,7 +33,8 @@ testing = [
 ]
 docs = [
     "sphinx",
-    "sphinx-book-theme",
+    "pydata-sphinx-theme==0.15.4",
+    "sphinx-book-theme==1.1.3",  # workaround for https://github.com/executablebooks/sphinx-book-theme/issues/865
     "myst-parser",
     "sphinx_design",
     "sphinx_autodoc_typehints",