diff --git a/docs/_static/custom.css b/docs/_static/custom.css
new file mode 100644
index 0000000..9a86294
--- /dev/null
+++ b/docs/_static/custom.css
@@ -0,0 +1,5 @@
+div.sphinxsidebar {
+	max-height: calc(100% - 30px);
+	overflow-y: auto;
+	overflow-x: hidden;
+}