Move clean-css to npm scripts.

Gruntfile.js

@@ -147,36 +147,6 @@ module.exports = function (grunt) {
     },
 
     // CSS build configuration
-    cssmin: {
-      options: {
-        sourceMap: true,
-        // sourceMapInlineSources: true,
-        advanced: false
-      },
-      core: {
-        files: [
-          {
-            expand: true,
-            cwd: 'dist/css',
-            src: ['*.css', '!*.min.css'],
-            dest: 'dist/css',
-            ext: '.min.css'
-          }
-        ]
-      },
-      docs: {
-        files: [
-          {
-            expand: true,
-            cwd: 'docs/assets/css',
-            src: ['*.css', '!*.min.css'],
-            dest: 'docs/assets/css',
-            ext: '.min.css'
-          }
-        ]
-      }
-    },
-
     copy: {
       docs: {
         expand: true,
@@ -260,6 +230,12 @@ module.exports = function (grunt) {
     },
 
     exec: {
+      'clean-css': {
+        command: 'npm run clean-css'
+      },
+      'clean-css-docs': {
+        command: 'npm run clean-css-docs'
+      },
       postcss: {
         command: 'npm run postcss'
       },
@@ -371,7 +347,7 @@ module.exports = function (grunt) {
   // grunt.registerTask('sass-compile', ['sass:core', 'sass:extras', 'sass:docs']);
   grunt.registerTask('sass-compile', ['sass:core', 'sass:extras', 'sass:docs']);
 
-  grunt.registerTask('dist-css', ['sass-compile', 'exec:postcss', 'cssmin:core', 'cssmin:docs']);
+  grunt.registerTask('dist-css', ['sass-compile', 'exec:postcss', 'exec:clean-css', 'exec:clean-css-docs']);
 
   // Full distribution task.
   grunt.registerTask('dist', ['clean:dist', 'dist-css', 'dist-js']);
@@ -380,7 +356,7 @@ module.exports = function (grunt) {
   grunt.registerTask('default', ['clean:dist', 'test']);
 
   // Docs task.
-  grunt.registerTask('docs-css', ['cssmin:docs', 'exec:postcss-docs']);
+  grunt.registerTask('docs-css', ['exec:clean-css-docs', 'exec:postcss-docs']);
   grunt.registerTask('lint-docs-css', ['exec:scss-lint-docs']);
   grunt.registerTask('docs-js', ['uglify:docsJs']);
   grunt.registerTask('docs', ['lint-docs-css', 'docs-css', 'docs-js', 'clean:docs', 'copy:docs']);