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#Using compass-rails with rails 4

If you try to use compass-rails with rails 4, the following error will stop you,

Unsupported rails environment for compass

You can fix this error by doing the following:

$ vim Gemfile
gem 'compass-rails', github: "milgner/compass-rails", branch: "rails4"

If the sprite images you generated with compass aren't being included, try this:

$ vim application.css.sass
@import "layout/*.png";
@include all-layout-sprites;

$ vim config/application.rb
config.compass.images_dir = '/app/assets/images'

With that, you should be able to precompile your assets!

For more details:

Compass/compass-rails#59

reference: http://threetreeslight.com/post/51303399725/rails4-compass-rails