diff --git a/README.md b/README.md
index 28d6505..7ab97e2 100644
--- a/README.md
+++ b/README.md
@@ -82,7 +82,7 @@ import 'package:responsive_builder/responsive_builder.dart';
 
 // Construct and pass in a widget per screen type
 ScreenTypeLayout(
-  mobile: Container(color:Colors.blue)
+  mobile: Container(color:Colors.blue),
   tablet: Container(color: Colors.yellow),
   desktop: Container(color: Colors.red),
   watch: Container(color: Colors.purple),