feat: apply iOS-style theme and replace removed color constants

Switch AppColors to iOS system palette (007AFF blue, F2F2F7 grouped
background, separator, label hierarchy) and rewrite AppTheme with
iOS-inspired Material 3 tokens (no elevation, negative letter-spacing,
50px buttons, 12px radii). Replace removed primaryLight/accent references
in recipe screens with primary.withValues(alpha:0.15) and primary.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/lib/core/theme/app_colors.dart

@@ -1,29 +1,28 @@
 import 'package:flutter/material.dart';
 
 abstract class AppColors {
-  // Primary
+  // iOS System Blue
-  static const primary = Color(0xFF4CAF50);
+  static const primary = Color(0xFF007AFF);
-  static const primaryLight = Color(0xFF81C784);
-  static const primaryDark = Color(0xFF388E3C);
 
-  // Accent
+  // Backgrounds — iOS grouped layout
-  static const accent = Color(0xFFFF9800);
+  static const background = Color(0xFFF2F2F7);   // systemGroupedBackground
+  static const surface = Color(0xFFFFFFFF);        // secondarySystemGroupedBackground
+  static const surfaceTertiary = Color(0xFFF2F2F7);
 
-  // Background
+  // Text — iOS label hierarchy
-  static const background = Color(0xFFF5F5F5);
+  static const textPrimary = Color(0xFF000000);   // label
-  static const surface = Color(0xFFFFFFFF);
+  static const textSecondary = Color(0xFF8E8E93); // secondaryLabel
 
-  // Text
+  // Separator
-  static const textPrimary = Color(0xFF212121);
+  static const separator = Color(0xFFC6C6C8);
-  static const textSecondary = Color(0xFF757575);
 
-  // Status
+  // iOS System colors
-  static const error = Color(0xFFE53935);
+  static const error = Color(0xFFFF3B30);         // systemRed
-  static const warning = Color(0xFFFFA726);
+  static const warning = Color(0xFFFF9500);        // systemOrange
-  static const success = Color(0xFF66BB6A);
+  static const success = Color(0xFF34C759);        // systemGreen
 
-  // Shelf life indicators
+  // Shelf life indicators (same as system colors)
-  static const freshGreen = Color(0xFF4CAF50);
+  static const freshGreen = Color(0xFF34C759);
-  static const warningYellow = Color(0xFFFFC107);
+  static const warningYellow = Color(0xFFFF9500);
-  static const expiredRed = Color(0xFFE53935);
+  static const expiredRed = Color(0xFFFF3B30);
 }

client/lib/core/theme/app_theme.dart

@@ -1,30 +1,255 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 import 'app_colors.dart';
 
 ThemeData appTheme() {
+  final base = ColorScheme.fromSeed(
+    seedColor: AppColors.primary,
+    brightness: Brightness.light,
+    surface: AppColors.surface,
+    onSurface: AppColors.textPrimary,
+  ).copyWith(
+    primary: AppColors.primary,
+    onPrimary: Colors.white,
+    secondary: AppColors.primary,
+    onSecondary: Colors.white,
+    tertiary: AppColors.primary,
+    error: AppColors.error,
+    surfaceContainerHighest: AppColors.surfaceTertiary,
+    onSurfaceVariant: AppColors.textSecondary,
+    outline: AppColors.separator,
+  );
+
   return ThemeData(
     useMaterial3: true,
-    colorSchemeSeed: AppColors.primary,
+    colorScheme: base,
     scaffoldBackgroundColor: AppColors.background,
+
+    // ── AppBar ────────────────────────────────────────
     appBarTheme: const AppBarTheme(
       centerTitle: true,
       elevation: 0,
-      backgroundColor: AppColors.surface,
+      scrolledUnderElevation: 0,
+      backgroundColor: AppColors.background,
       foregroundColor: AppColors.textPrimary,
+      systemOverlayStyle: SystemUiOverlayStyle(
+        statusBarBrightness: Brightness.light,
+        statusBarIconBrightness: Brightness.dark,
       ),
+      titleTextStyle: TextStyle(
+        color: AppColors.textPrimary,
+        fontSize: 17,
+        fontWeight: FontWeight.w600,
+        letterSpacing: -0.4,
+      ),
+    ),
+
+    // ── Card ──────────────────────────────────────────
+    // iOS: white cards on grey background, no shadow
+    cardTheme: CardThemeData(
+      elevation: 0,
+      color: AppColors.surface,
+      surfaceTintColor: Colors.transparent,
+      shape: RoundedRectangleBorder(
+        borderRadius: BorderRadius.circular(12),
+      ),
+    ),
+
+    // ── Bottom navigation ─────────────────────────────
     bottomNavigationBarTheme: const BottomNavigationBarThemeData(
+      backgroundColor: AppColors.surface,
       selectedItemColor: AppColors.primary,
       unselectedItemColor: AppColors.textSecondary,
       type: BottomNavigationBarType.fixed,
+      elevation: 0,
+      selectedLabelStyle: TextStyle(
+        fontSize: 10,
+        fontWeight: FontWeight.w500,
+        letterSpacing: -0.2,
+      ),
+      unselectedLabelStyle: TextStyle(fontSize: 10),
+    ),
+
+    // ── Buttons ───────────────────────────────────────
+    filledButtonTheme: FilledButtonThemeData(
+      style: FilledButton.styleFrom(
+        minimumSize: const Size(double.infinity, 50),
+        backgroundColor: AppColors.primary,
+        foregroundColor: Colors.white,
+        elevation: 0,
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(12),
+        ),
+        textStyle: const TextStyle(
+          fontSize: 17,
+          fontWeight: FontWeight.w600,
+          letterSpacing: -0.3,
+        ),
       ),
-    inputDecorationTheme: InputDecorationTheme(
-      border: OutlineInputBorder(borderRadius: BorderRadius.circular(12)),
-      contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
     ),
     elevatedButtonTheme: ElevatedButtonThemeData(
       style: ElevatedButton.styleFrom(
-        minimumSize: const Size(double.infinity, 48),
+        minimumSize: const Size(double.infinity, 50),
-        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
+        elevation: 0,
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(12),
+        ),
+      ),
+    ),
+    outlinedButtonTheme: OutlinedButtonThemeData(
+      style: OutlinedButton.styleFrom(
+        minimumSize: const Size(double.infinity, 50),
+        side: const BorderSide(color: AppColors.primary),
+        shape: RoundedRectangleBorder(
+          borderRadius: BorderRadius.circular(12),
+        ),
+        textStyle: const TextStyle(
+          fontSize: 17,
+          fontWeight: FontWeight.w400,
+          letterSpacing: -0.3,
+        ),
+      ),
+    ),
+
+    // ── Inputs ────────────────────────────────────────
+    inputDecorationTheme: InputDecorationTheme(
+      filled: true,
+      fillColor: AppColors.surface,
+      border: OutlineInputBorder(
+        borderRadius: BorderRadius.circular(10),
+        borderSide: const BorderSide(color: AppColors.separator),
+      ),
+      enabledBorder: OutlineInputBorder(
+        borderRadius: BorderRadius.circular(10),
+        borderSide: const BorderSide(color: AppColors.separator),
+      ),
+      focusedBorder: OutlineInputBorder(
+        borderRadius: BorderRadius.circular(10),
+        borderSide: const BorderSide(color: AppColors.primary, width: 1.5),
+      ),
+      errorBorder: OutlineInputBorder(
+        borderRadius: BorderRadius.circular(10),
+        borderSide: const BorderSide(color: AppColors.error),
+      ),
+      contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
+      hintStyle: const TextStyle(color: AppColors.textSecondary),
+    ),
+
+    // ── ListTile ──────────────────────────────────────
+    listTileTheme: const ListTileThemeData(
+      contentPadding: EdgeInsets.symmetric(horizontal: 16),
+      minVerticalPadding: 12,
+    ),
+
+    // ── Divider ───────────────────────────────────────
+    dividerTheme: const DividerThemeData(
+      color: AppColors.separator,
+      space: 1,
+      thickness: 0.5,
+      indent: 16,
+    ),
+
+    // ── Chip ──────────────────────────────────────────
+    chipTheme: ChipThemeData(
+      shape: RoundedRectangleBorder(
+        borderRadius: BorderRadius.circular(20),
+      ),
+      side: const BorderSide(color: AppColors.separator),
+    ),
+
+    // ── Dialog ───────────────────────────────────────
+    dialogTheme: DialogThemeData(
+      backgroundColor: AppColors.surface,
+      surfaceTintColor: Colors.transparent,
+      elevation: 0,
+      shape: RoundedRectangleBorder(
+        borderRadius: BorderRadius.circular(14),
+      ),
+    ),
+
+    // ── Bottom sheet ─────────────────────────────────
+    bottomSheetTheme: const BottomSheetThemeData(
+      backgroundColor: AppColors.surface,
+      surfaceTintColor: Colors.transparent,
+      elevation: 0,
+      shape: RoundedRectangleBorder(
+        borderRadius: BorderRadius.vertical(top: Radius.circular(12)),
+      ),
+    ),
+
+    // ── Text ─────────────────────────────────────────
+    textTheme: const TextTheme(
+      headlineLarge: TextStyle(
+        fontSize: 34,
+        fontWeight: FontWeight.w700,
+        letterSpacing: -0.5,
+        color: AppColors.textPrimary,
+      ),
+      headlineMedium: TextStyle(
+        fontSize: 28,
+        fontWeight: FontWeight.w700,
+        letterSpacing: -0.4,
+        color: AppColors.textPrimary,
+      ),
+      headlineSmall: TextStyle(
+        fontSize: 22,
+        fontWeight: FontWeight.w700,
+        letterSpacing: -0.3,
+        color: AppColors.textPrimary,
+      ),
+      titleLarge: TextStyle(
+        fontSize: 20,
+        fontWeight: FontWeight.w600,
+        letterSpacing: -0.3,
+        color: AppColors.textPrimary,
+      ),
+      titleMedium: TextStyle(
+        fontSize: 17,
+        fontWeight: FontWeight.w600,
+        letterSpacing: -0.3,
+        color: AppColors.textPrimary,
+      ),
+      titleSmall: TextStyle(
+        fontSize: 15,
+        fontWeight: FontWeight.w600,
+        letterSpacing: -0.2,
+        color: AppColors.textPrimary,
+      ),
+      bodyLarge: TextStyle(
+        fontSize: 17,
+        fontWeight: FontWeight.w400,
+        letterSpacing: -0.3,
+        color: AppColors.textPrimary,
+      ),
+      bodyMedium: TextStyle(
+        fontSize: 15,
+        fontWeight: FontWeight.w400,
+        letterSpacing: -0.2,
+        color: AppColors.textPrimary,
+      ),
+      bodySmall: TextStyle(
+        fontSize: 13,
+        fontWeight: FontWeight.w400,
+        letterSpacing: -0.1,
+        color: AppColors.textSecondary,
+      ),
+      labelLarge: TextStyle(
+        fontSize: 15,
+        fontWeight: FontWeight.w500,
+        letterSpacing: -0.2,
+        color: AppColors.textPrimary,
+      ),
+      labelMedium: TextStyle(
+        fontSize: 13,
+        fontWeight: FontWeight.w500,
+        letterSpacing: -0.1,
+        color: AppColors.textPrimary,
+      ),
+      labelSmall: TextStyle(
+        fontSize: 11,
+        fontWeight: FontWeight.w400,
+        letterSpacing: 0,
+        color: AppColors.textSecondary,
       ),
     ),
   );

client/lib/features/recipes/recipe_detail_screen.dart

@@ -194,7 +194,7 @@ class _RecipeDetailScreenState extends ConsumerState<RecipeDetailScreen> {
 class _PlaceholderImage extends StatelessWidget {
   @override
   Widget build(BuildContext context) => Container(
-        color: AppColors.primaryLight.withValues(alpha: 0.3),
+        color: AppColors.primary.withValues(alpha: 0.15),
         child: const Center(child: Icon(Icons.restaurant, size: 64)),
       );
 }
@@ -293,7 +293,7 @@ class _NutritionCard extends StatelessWidget {
                   child: Text(
                     '≈',
                     style: TextStyle(
-                      color: AppColors.accent,
+                      color: AppColors.primary,
                       fontSize: 16,
                       fontWeight: FontWeight.bold,
                     ),
@@ -360,7 +360,7 @@ class _TagsRow extends StatelessWidget {
           .map(
             (t) => Chip(
               label: Text(t, style: const TextStyle(fontSize: 11)),
-              backgroundColor: AppColors.primaryLight.withValues(alpha: 0.3),
+              backgroundColor: AppColors.primary.withValues(alpha: 0.15),
               padding: EdgeInsets.zero,
               visualDensity: VisualDensity.compact,
             ),
@@ -490,12 +490,12 @@ class _StepTile extends StatelessWidget {
                   Row(
                     children: [
                       const Icon(Icons.timer_outlined,
-                          size: 14, color: AppColors.accent),
+                          size: 14, color: AppColors.primary),
                       const SizedBox(width: 4),
                       Text(
                         _formatTimer(step.timerSeconds!),
                         style: const TextStyle(
-                            color: AppColors.accent, fontSize: 12),
+                            color: AppColors.primary, fontSize: 12),
                       ),
                     ],
                   ),

client/lib/features/recipes/saved_recipes_screen.dart

@@ -197,7 +197,7 @@ class _Thumbnail extends StatelessWidget {
       return Container(
         width: 80,
         height: 80,
-        color: AppColors.primaryLight.withValues(alpha: 0.3),
+        color: AppColors.primary.withValues(alpha: 0.15),
         child: const Icon(Icons.restaurant),
       );
     }
@@ -211,7 +211,7 @@ class _Thumbnail extends StatelessWidget {
       errorWidget: (_, __, ___) => Container(
         width: 80,
         height: 80,
-        color: AppColors.primaryLight.withValues(alpha: 0.3),
+        color: AppColors.primary.withValues(alpha: 0.15),
         child: const Icon(Icons.restaurant),
       ),
     );

client/lib/features/recipes/widgets/recipe_card.dart

@@ -125,7 +125,7 @@ class _RecipeImage extends StatelessWidget {
     if (imageUrl.isEmpty) {
       return Container(
         height: 180,
-        color: AppColors.primaryLight.withValues(alpha: 0.3),
+        color: AppColors.primary.withValues(alpha: 0.15),
         child: const Center(child: Icon(Icons.restaurant, size: 48)),
       );
     }
@@ -140,7 +140,7 @@ class _RecipeImage extends StatelessWidget {
       ),
       errorWidget: (_, __, ___) => Container(
         height: 180,
-        color: AppColors.primaryLight.withValues(alpha: 0.3),
+        color: AppColors.primary.withValues(alpha: 0.15),
         child: const Center(child: Icon(Icons.restaurant, size: 48)),
       ),
     );
@@ -235,7 +235,7 @@ class _NutritionRow extends StatelessWidget {
         );
     return Row(
       children: [
-        Text('≈ ', style: style?.copyWith(color: AppColors.accent)),
+        Text('≈ ', style: style?.copyWith(color: AppColors.primary)),
         _NutItem(label: 'ккал', value: nutrition.calories.round(), style: style),
         const SizedBox(width: 8),
         _NutItem(label: 'б', value: nutrition.proteinG.round(), style: style),