Setting theme data for flutter app seems broken - flutter

Question

I've tried everything I can think of to change the background color of my flutter app, but every time I run the app, the background is black.
This is main.dart
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'auth_controller.dart';
import 'themes/color.dart';
import 'index.dart';
Future<void> main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp().then((value) => Get.put(AuthController));
runApp(MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
//ThemeData
title: 'Title',
theme: ThemeData(
brightness: Brightness.light,
),
home:const Index(),
debugShowCheckedModeBanner: false,
);
}
}
I don't think I'm even using themes/color.dart but I thought I'd leave it in anyway. Brightness should set it.
This is index.dart
import 'package:flutter/material.dart';
import 'themes/color.dart';
import 'signup.dart';
Future<void> main() async {
runApp(MyApp(
routes: <String, WidgetBuilder>{
'/signup': (BuildContext context) => const SignUp()
},
debugShowCheckedModeBanner: false,
));
}
class MyApp extends StatelessWidget {
const MyApp({Key? key, required Map<String, WidgetBuilder> routes, required bool debugShowCheckedModeBanner}) : super(key: key);
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Welcome to Flutter',
home: Scaffold(
backgroundColor: const Color(0xFFe3e4e4),
appBar: AppBar(
title: const Text('Flutter Screen Background Color Example'),
),
body: const Center(child: Index()),
),
);
}
}
class Index extends StatelessWidget {
const Index({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
const SizedBox(height: 20,),
ElevatedButton(
child: const Text('WTF'),
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const SignUp()),
);
}
),
]
)
);
}
}
It seems like the background should be a light grey,but it's black. I tried invalidating the caches and restarting too.