Index: Gruntfile.js
===================================================================
--- Gruntfile.js	(revision 26742)
+++ Gruntfile.js	(working copy)
@@ -147,7 +147,7 @@
 				dest: BUILD_DIR,
 				ext: '-rtl.css',
 				src: [
-					'wp-admin/css/colors/**/*.css'
+					'wp-admin/css/colors/{blue,light,midnight}/colors.css'
 				]
 			},
 			dynamic: {