diff --git a/package.json b/package.json
index d6556c3..829d4be 100644
--- a/package.json
+++ b/package.json
@@ -58,7 +58,7 @@
   "devDependencies": {
     "autoprefixer": "^6.0.3",
     "browser-sync": "^2.9.11",
-    "clean-css": "^4.2.3",
+    "clean-css": "^5.1.4",
     "headr": "^0.1.0",
     "node-sass": "^3.4.1",
     "parallelshell": "^2.0.0",