error precompiling assets when moving to production

I am trying to move my project to production,
trying to

RAILS_ENV=production bundle exec rake assets:precompile

gives me an error, without specifying in which file it is.

rake aborted!
Sass::SyntaxError: Invalid CSS after "}": expected selector or at-rule, was "}"
(sass):89
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sass-3.4.23/lib/sass/scss/parser.rb:1207:in `expected'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sass-3.4.23/lib/sass/scss/parser.rb:1137:in `expected'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sass-3.4.23/lib/sass/scss/parser.rb:42:in `parse'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sass-3.4.23/lib/sass/engine.rb:406:in `_to_tree'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sass-3.4.23/lib/sass/engine.rb:281:in `render'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sprockets-3.7.1/lib/sprockets/sass_compressor.rb:48:in `call'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sprockets-3.7.1/lib/sprockets/sass_compressor.rb:28:in `call'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:75:in `call_processor'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:57:in `block in call_processors'
/Users/mac/.rvm/gems/ruby-2.2.3/gems/sprockets-3.7.1/lib/sprockets/processor_utils.rb:56:in `reverse_each'

how do I findout in which file that error occurs? even with --trace it doesnt tell me.