diff --git a/conf.py b/conf.py
index 85ec73d..efa934c 100644
--- a/conf.py
+++ b/conf.py
@@ -181,8 +181,8 @@
 
 def setup(app):
    #app.add_javascript("custom.js")
-   app.add_stylesheet("css/main.css")
-   app.add_stylesheet("css/pdf/ospdf.style")
+   app.add_css_file("css/main.css")
+   app.add_css_file("css/pdf/ospdf.style")
 
 # Add any extra paths that contain custom files (such as robots.txt or
 # .htaccess) here, relative to this directory. These files are copied