diff --git a/docs/providers/custom.rst b/docs/providers/custom.rst
index effd87fa..f1c77e1c 100644
--- a/docs/providers/custom.rst
+++ b/docs/providers/custom.rst
@@ -1,5 +1,5 @@
 Writing of custom providers
-------------------------
+---------------------------
 
 .. module:: dependency_injector.providers