main, change layout so that minutes cannot be modified while the alarm is enabled, also handle validation better.

lib/main.dart

@@ -66,6 +66,9 @@ class _HomeScreenState extends State<HomeScreen> {
   int _minutesBefore = 30;
   bool _loading = false;
 
+  String? _sunsetErrorText = null;
+  String? _minuteErrorText = null;
+
   static const _alarmId = 1001;
 
   @override
@@ -426,40 +429,46 @@ class _HomeScreenState extends State<HomeScreen> {
             // --- Minutes before ---
             Row(
               children: [
-                const Text('Minutes before: '),
-                SizedBox(
-                  width: 80,
+                if (!_alarmEnabled)
+                  Expanded(
                     child: TextField(
                       controller: _minutesController,
                       keyboardType: TextInputType.number,
-                    decoration: const InputDecoration(
+                      decoration: InputDecoration(
                         border: OutlineInputBorder(),
+                        labelText: 'Minutes Before Sunset',
+                        errorText: _minuteErrorText,
                       ),
                       onChanged: (v) {
                         final val = int.tryParse(v);
-                      if (val != null && val >= 0) {
+                        setState(() {
+                          if (val != null) {
+                            _minuteErrorText = null;
                             _minutesBefore = val;
                           } else {
-                        _showSnack('Invalid Minute Value');
+                            _minuteErrorText = 'Invalid Minute Value';
                           }
+                        });
                       },
                     ),
                   ),
-              ],
-            ),
-            const SizedBox(height: 24),
 
                 // --- Toggle ---
-            SwitchListTile(
-              title: const Text('Enable Sunset Alarm'),
+                Expanded(
+                  child: SwitchListTile(
+                    //title: const Text('Enable Sunset Alarm'),
+                    title: Text(_alarmEnabled ? 'Sunset Alarm Enabled' : ''),
                     subtitle: Text(
                       _alarmEnabled
                           ? 'Will alert ${_minutesBefore} min before sunset. ($_alarmDisplayTime)'
-                    : 'Alarm is off',
+                          : '',
                     ),
                     value: _alarmEnabled,
                     onChanged: _toggleAlarm,
                   ),
+                ),
+              ],
+            ),
           ],
         ),
       ),