diff --git a/dwsd/_extensions/drwater/dwsd/_extension.yml b/dwsd/_extensions/drwater/dwsd/_extension.yml
index 279de41..2300c86 100644
--- a/dwsd/_extensions/drwater/dwsd/_extension.yml
+++ b/dwsd/_extensions/drwater/dwsd/_extension.yml
@@ -5,7 +5,8 @@ quarto-required: ">=1.3.0"
 contributes:
   formats:
     revealjs:
-      theme: [default, dwsd.css]
+      theme: [default]
+      css: dwsd.css
       slide-number: true
       date-format: long
       logo: rceeslogo.png