main, ensure the alarm time gets changed if modified when already enabled.

lib/main.dart

@@ -30,12 +30,22 @@ class SunsetAlarmApp extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    const seedColor = Colors.deepOrange;
     return MaterialApp(
       title: 'Sunset Alarm',
       theme: ThemeData(
-        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepOrange),
-        useMaterial3: true,
+        colorScheme: ColorScheme.fromSeed(
+          seedColor: seedColor,
+          brightness: Brightness.light,
+        ),
       ),
+      darkTheme: ThemeData(
+        colorScheme: ColorScheme.fromSeed(
+          seedColor: seedColor,
+          brightness: Brightness.dark,
+        ),
+      ),
+      themeMode: ThemeMode.system,
       home: const HomeScreen(),
     );
   }
@@ -288,6 +298,7 @@ class _HomeScreenState extends State<HomeScreen> {
       );
       await Alarm.set(alarmSettings: settings);
       // End Alarm Method ***/
+      _showSnack('Alarm Scheduled @ ${alarmTime}');
     } else {
       _showSnack('Platform not detected, unsure how to show alarm.');
     }
@@ -431,6 +442,9 @@ class _HomeScreenState extends State<HomeScreen> {
                       final val = _validateTime(v);
                       if (val == null) {
                         _savePrefs();
+                        if (_alarmEnabled) {
+                          _scheduleAlarm();
+                        }
                       }
                       setState(() {
                         _sunsetErrorText = val;
@@ -449,7 +463,14 @@ class _HomeScreenState extends State<HomeScreen> {
                           )
                           : const Icon(Icons.cloud_done_outlined),
                   tooltip: 'Fetch Sunset Time from Open-Meteo',
-                  onPressed: _loading ? null : _fetchSunset,
+                  onPressed: () {
+                    if (!_loading) {
+                      _fetchSunset();
+                      if (_alarmEnabled) {
+                        _scheduleAlarm();
+                      }
+                    }
+                  },
                 ),
               ],
             ),