diff --git a/Gruntfile.js b/Gruntfile.js
index ca9d43eec4..3301329ecb 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -180,7 +180,16 @@ module.exports = function (grunt) {
 
     autoprefixer: {
       options: {
-        browsers: ['last 2 versions', 'ie 8', 'ie 9', 'android 2.3', 'android 4', 'opera 12']
+        browsers: [
+          'Android 2.3',
+          'Android >= 4',
+          'Chrome >= 20',
+          'Firefox >= 24', // Firefox 24 is the latest ESR
+          'Explorer >= 8',
+          'iOS >= 6',
+          'Opera >= 12',
+          'Safari >= 6'
+        ]
       },
       core: {
         options: {