diff --git a/docs/customization/simple.md b/docs/customization/simple.md
index 3160dc8..964c3f1 100644
--- a/docs/customization/simple.md
+++ b/docs/customization/simple.md
@@ -95,7 +95,7 @@ _Example: Add LESS loading to the project._
       "module": {
         "rule": {
           "styles": {
-            "test": "/\\.less$/",
+            "test": "\\.less$",
             "loader": {
               "less": {
                 "loader": "less-loader",