[Solved] File to import not found or unreadable: compass/css3

I'm on Windows 8 and I tried installing sass and compass and when I tried "compass watch" on an existing project which has an "@import "compass/css3";, I got an error:  File to import not found or unreadable: compass/css3

The solution is to install rails-compass

gem install compass-rails

After that "compass watch" now worked.