Rails Sass: variables are not passed with @import

Try removing *= require_tree from your application.css.scss. Using require doesn't work well with sass files, especially when combined with @import.

Don't forget to import/require your main.scss file when you remove require_tree.

https://github.com/rails/sass-rails#important-note

Noting above, I've recently had some experience with assets not working as expected. The recommendation I received was to use:

rake assets:clobber

This will clean up the pipeline.

https://github.com/rails/sprockets-rails/blob/master/README.md