rails:assets_precompile not working although working locally or via SSH

[mmics]

rails:assets_precompile gives me a Sass::SyntaxError: Invalid CSS after "...
When I invoke rails assets:precompile locally it works
When I SSH into the deploy target host and invoke RAILS_ENV="production" bundle exec rake assets:precompile it works, too

config.assets.css_compressor = :sass is disabled in the config/production.rb file.

I am using mina 1.0.7, rails (4.2.8), sass (3.5.1)

I have been trying to fix this issue for quite a while without success. I am not able to locate any CSS syntax errors in my code.

[mmics]

There was an error in my css syntax. I finally found it using scss-lint scss-lint app/assets/stylesheets/ |grep "\[E\]".