diff --git a/book.toml b/book.toml
index 6f4fbd3..a648703 100644
--- a/book.toml
+++ b/book.toml
@@ -4,3 +4,6 @@ language = "en"
 multilingual = false
 src = "src"
 title = "SelfPrivacy Docs"
+
+[output.html]
+default-theme = "navy"