Mobile and web versions

lib/components/app_bar.dart

@@ -6,7 +6,7 @@ class GymLinkAppBar extends StatelessWidget implements PreferredSizeWidget {
   @override
   Widget build(BuildContext context) {
     return AppBar(
-      backgroundColor: Colors.white,
+      backgroundColor: Theme.of(context).scaffoldBackgroundColor,
       shadowColor: null,
       automaticallyImplyLeading: false,
       elevation: 0,