diff --git a/manual/conversion.rst b/manual/conversion.rst
index 88381b1455..776cb38c61 100644
--- a/manual/conversion.rst
+++ b/manual/conversion.rst
@@ -905,7 +905,7 @@ then the PDF Outline provides this functionality and is generated by default.
 
 You can customize the look of the generated Table of contents by using the
 Extra CSS conversion setting under the Look & feel part of the conversion
-dialog. The default css used is listed below, simply copy it and make whatever
+dialog. The default CSS used is listed below, simply copy it and make whatever
 changes you like.
 
 .. code-block:: css