Setup Less paths for imports

middleman-core/lib/middleman-core/renderers/less.rb

@@ -17,6 +17,10 @@ module Middleman
           app.before_configuration do
             template_extensions :less => :css
           end
+          
+          app.after_configuration do
+            ::Less.paths << File.expand_path(css_dir, source_dir)
+          end
 
           # Tell Tilt to use it as well (for inline sass blocks)
           ::Tilt.register 'less', LocalLoadingLessTemplate