Enhance navigation and structure: integrate SettingsScreen into main app flow, update HomeScreen to open settings, and improve UI elements for better user experience.

lib/app.dart

@@ -7,6 +7,7 @@ import 'package:notas/data/note_repository.dart';
 import 'package:notas/platform/app_platform.dart';
 import 'package:notas/platform/window_state.dart';
 import 'package:notas/screens/home_screen.dart';
+import 'package:notas/screens/settings_screen.dart';
 import 'package:notas/screens/vault_access_screen.dart';
 import 'package:notas/theme/app_theme.dart';
 import 'package:notas/widgets/app_title_bar.dart';
@@ -14,6 +15,11 @@ import 'package:path/path.dart' as p;
 import 'package:path_provider/path_provider.dart';
 import 'package:window_manager/window_manager.dart';
 
+enum _AppSection {
+  home,
+  settings,
+}
+
 class NotesApp extends StatefulWidget {
   const NotesApp({super.key});
 
@@ -22,6 +28,8 @@ class NotesApp extends StatefulWidget {
 }
 
 class _NotesAppState extends State<NotesApp> with WindowListener {
+  static const Duration _screenTransitionDuration = Duration(milliseconds: 280);
+
   final LocalVaultService _vaultService = LocalVaultService.instance;
   final GlobalKey<ScaffoldMessengerState> _scaffoldMessengerKey =
       GlobalKey<ScaffoldMessengerState>();
@@ -30,6 +38,7 @@ class _NotesAppState extends State<NotesApp> with WindowListener {
   NoteRepository? _repository;
   bool _isBootstrapping = true;
   bool _isUnlocking = false;
+  _AppSection _currentSection = _AppSection.home;
 
   @override
   void initState() {
@@ -80,6 +89,26 @@ class _NotesAppState extends State<NotesApp> with WindowListener {
     });
   }
 
+  void _openSettings() {
+    if (!mounted) {
+      return;
+    }
+
+    setState(() {
+      _currentSection = _AppSection.settings;
+    });
+  }
+
+  void _openHome() {
+    if (!mounted) {
+      return;
+    }
+
+    setState(() {
+      _currentSection = _AppSection.home;
+    });
+  }
+
   Future<void> _resetLocalVaultData() async {
     final AppDatabase? database = _database;
 
@@ -207,6 +236,68 @@ class _NotesAppState extends State<NotesApp> with WindowListener {
     );
   }
 
+  Widget _buildMainShell(NoteRepository repository) {
+    final Widget activeScreen = _currentSection == _AppSection.home
+        ? HomeScreen(
+            key: const ValueKey<String>('home-screen'),
+            repository: repository,
+            onOpenSettings: _openSettings,
+          )
+        : SettingsScreen(
+            key: const ValueKey<String>('settings-screen'),
+            onDeleteAllData: _resetLocalVaultData,
+            onBackToHome: _openHome,
+          );
+
+    return MaterialApp(
+      title: 'Mis Notas',
+      debugShowCheckedModeBanner: false,
+      scaffoldMessengerKey: _scaffoldMessengerKey,
+      theme: AppTheme.theme,
+      home: Scaffold(
+        body: Container(
+          decoration: const BoxDecoration(
+            gradient: LinearGradient(
+              colors: [
+                Color(0xFF191A1D),
+                Color(0xFF222326),
+                Color(0xFF101114),
+              ],
+              begin: Alignment.topLeft,
+              end: Alignment.bottomRight,
+            ),
+          ),
+          child: SafeArea(
+            child: Column(
+              children: [
+                const AppTitleBar(),
+                Expanded(
+                  child: AnimatedSwitcher(
+                    duration: _screenTransitionDuration,
+                    switchInCurve: Curves.easeOutCubic,
+                    switchOutCurve: Curves.easeInCubic,
+                    transitionBuilder: (Widget child, Animation<double> animation) {
+                      final Animation<Offset> offsetAnimation = Tween<Offset>(
+                        begin: const Offset(0.08, 0.0),
+                        end: Offset.zero,
+                      ).animate(animation);
+
+                      return FadeTransition(
+                        opacity: animation,
+                        child: SlideTransition(position: offsetAnimation, child: child),
+                      );
+                    },
+                    child: activeScreen,
+                  ),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
   @override
   void onWindowResize() {
     _saveWindowSize();
@@ -226,12 +317,7 @@ class _NotesAppState extends State<NotesApp> with WindowListener {
     final NoteRepository? repository = _repository;
 
     if (repository != null) {
-      return _buildAppShell(
-        home: HomeScreen(
-          repository: repository,
-          onDeleteAllData: _resetLocalVaultData,
-        ),
-      );
+      return _buildMainShell(repository);
     }
 
     return _buildAppShell(