add vienna social housing theme (brown)

wien_talks/wien_talks_flutter/lib/main.dart

@@ -1,6 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_dotenv/flutter_dotenv.dart';
 import 'package:wien_talks_flutter/helper/go_router.dart';
+import 'package:wien_talks_flutter/theme.dart';
 
 Future<void> main() async {
   await dotenv.load(fileName: '.env');
@@ -14,7 +15,7 @@ class MyApp extends StatelessWidget {
   Widget build(BuildContext context) {
     return MaterialApp.router(
       title: 'Wien Talks',
-      theme: ThemeData(primarySwatch: Colors.green),
+      theme: GemeindeBauTheme.light(),
       routerConfig: router,
     );
   }

wien_talks/wien_talks_flutter/lib/theme.dart

@@ -0,0 +1,79 @@
+import 'package:flutter/material.dart';
+
+class GemeindeBauTheme {
+  static const _brand = Color(0xFFE20613);
+  static const _accent = Color(0xFF009640);
+  static const _radius = 14.0;
+
+  static ThemeData light() => _base(
+        ColorScheme.fromSeed(
+          seedColor: _brand,
+          brightness: Brightness.light,
+        ).copyWith(
+          secondary: _accent,
+        ),
+      );
+
+  static ThemeData _base(
+    ColorScheme scheme,
+  ) {
+    return ThemeData(
+      useMaterial3: true,
+      colorScheme: scheme,
+      scaffoldBackgroundColor: scheme.surface,
+      appBarTheme: AppBarTheme(
+        backgroundColor: scheme.surface,
+        foregroundColor: scheme.onSurface,
+        elevation: 0.5,
+        // surfaceTintColor: Colors.transparent,
+        centerTitle: false,
+      ),
+      bottomSheetTheme: BottomSheetThemeData(
+        backgroundColor: scheme.surface,
+        shape: RoundedRectangleBorder(
+          borderRadius:
+              const BorderRadius.vertical(top: Radius.circular(_radius)),
+        ),
+      ),
+      floatingActionButtonTheme: FloatingActionButtonThemeData(
+        backgroundColor: scheme.primary,
+        foregroundColor: scheme.onPrimary,
+        elevation: 3,
+        shape: const StadiumBorder(),
+      ),
+      inputDecorationTheme: InputDecorationTheme(
+        filled: true,
+        fillColor: scheme.surfaceContainerHighest,
+        border: OutlineInputBorder(
+          borderRadius: BorderRadius.circular(12),
+          borderSide: BorderSide(color: scheme.outlineVariant),
+        ),
+        enabledBorder: OutlineInputBorder(
+          borderRadius: BorderRadius.circular(12),
+          borderSide: BorderSide(color: scheme.outlineVariant),
+        ),
+        focusedBorder: OutlineInputBorder(
+          borderRadius: BorderRadius.circular(12),
+          borderSide: BorderSide(color: scheme.primary, width: 2),
+        ),
+        contentPadding:
+            const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
+      ),
+      listTileTheme: ListTileThemeData(
+        iconColor: scheme.onSurfaceVariant,
+        textColor: scheme.onSurface,
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(12),
+        ),
+      ),
+      snackBarTheme: SnackBarThemeData(
+        backgroundColor: scheme.inverseSurface,
+        contentTextStyle: TextStyle(color: scheme.onInverseSurface),
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(12),
+        ),
+      ),
+      dividerColor: scheme.outlineVariant,
+    );
+  }
+}