diff --git a/Gruntfile.js b/Gruntfile.js
index a4c48ea..dbc05e0 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -2,79 +2,78 @@ module.exports = function(grunt) {
 
   require('load-grunt-tasks')(grunt);
 
-  pkg: grunt.file.readJSON('package.json'),
+  var concatAnim;
+
   grunt.initConfig({
 
-    // Concatenate CSS files
+    pkg: grunt.file.readJSON('package.json'),
+
     concat: {
       dist: {
-        src: [
-          // _base.css required for .animated helper class
-          'source/_base.css',
-          'source/**/*.css'
-        ],
+        src: [ 'source/_base.css', 'source/**/*.css' ], // _base.css required for .animated helper class
         dest: 'animate.css'
       }
     },
 
-    // Auto-prefix CSS properties using Can I Use?
-    autoprefixer: {
+    autoprefixer: { // https://github.com/nDmitry/grunt-autoprefixer
       options: {
         browsers: ['last 3 versions', 'bb 10', 'android 3']
       },
       no_dest: {
-        // File to output
-        src: 'animate.css'
-      },
+        src: 'animate.css' // output file
+      }
     },
 
-    // Minify CSS
     cssmin: {
       minify: {
         src: ['animate.css'],
         dest: 'animate.min.css',
-      },
+      }
     },
 
-    // Watch files for changes
     watch: {
       css: {
-        files: [
-          'source/**/*',
-          '!node_modules',
-          'animate-config.json'
-        ],
-        // Run Sass, autoprefixer, and CSSO
-        tasks: ['concat-anim', 'autoprefixer', 'cssmin'],
+        files: [ 'source/**/*', 'animate-config.json' ],
+        tasks: ['default']
       }
     }
 
   });
 
-  // Register our tasks
-  grunt.registerTask('default', ['concat-anim', 'autoprefixer', 'cssmin', 'watch']);
+  // fuction to perform custom task
+  concatAnim = function () {
 
-  grunt.registerTask('concat-anim', 'Concatenates activated animations', function () {
-    var config = grunt.file.readJSON('animate-config.json'),
-        target = [ 'source/_base.css' ],
-        count = 0
+    var categories = grunt.file.readJSON('animate-config.json'),
+      category, files, file,
+      target = [ 'source/_base.css' ],
+      count = 0;
 
-    for (var cat in config) {
-      for (var file in config[cat]) {
-        if (config[cat][file]) {
-          target.push('source/' + cat + '/' + file + '.css')
-          count++
+    for ( category in categories ) {
+      if ( categories.hasOwnProperty(category) ) {
+        files = categories[category]
+        for (file in files) {
+          if ( files.hasOwnProperty(file) && files[file] ) {
+            target.push('source/' + category + '/' + file + '.css');
+            count += 1;
+          }
         }
       }
     }
 
     if (!count) {
-      grunt.log.writeln('No animations activated.')
+      grunt.log.writeln('No animations activated.');
+    } else {
+      grunt.log.writeln(count + (count > 1 ? ' animations' : ' animation') + ' activated.');
     }
 
-    grunt.log.writeln(count + (count > 1 ? ' animations' : ' animation') + ' activated.')
+    grunt.config('concat', { 'animate.css': target });
+    grunt.task.run('concat');
+
+  };
+
+  // register task
+  grunt.registerTask('concat-anim', 'Concatenates activated animations', concatAnim); // custom task
+  grunt.registerTask('default', ['concat-anim', 'autoprefixer', 'cssmin']);
+  grunt.registerTask('dev', ['watch']);
 
-    grunt.config('concat', { 'animate.css': target })
-    grunt.task.run('concat')
-  });
 };