diff --git a/lib/app.rb b/lib/app.rb
index e23b241c..158de64f 100644
--- a/lib/app.rb
+++ b/lib/app.rb
@@ -94,7 +94,7 @@ class App < Sinatra::Application
       ]
 
     sprockets.js_compressor = Terser.new
-    sprockets.css_compressor = :sass
+    sprockets.css_compressor = :sassc
 
     Sprockets::Helpers.configure do |config|
       config.digest = true