feat: 静态页面开发完成

lib/theme.dart

@@ -4,45 +4,106 @@ import 'package:google_fonts/google_fonts.dart';
 import 'package:flutter_animate/flutter_animate.dart';
 
 class AppColors {
+  // Brand colors (stable across light/dark)
   static const primary = Color(0xFF1A56DB);
   static const primaryLight = Color(0xFF3B82F6);
   static const primaryDark = Color(0xFF1E40AF);
   static const accent = Color(0xFF00C9A7);
   static const accentLight = Color(0xFF6EE7B7);
-  static const background = Color(0xFFF8FAFC);
-  static const surface = Colors.white;
   static const error = Color(0xFFEF4444);
   static const warning = Color(0xFFF59E0B);
   static const success = Color(0xFF10B981);
-  static const textPrimary = Color(0xFF1E293B);
-  static const textSecondary = Color(0xFF64748B);
-  static const textTertiary = Color(0xFF94A3B8);
-  static const divider = Color(0xFFE2E8F0);
-  static const cardShadow = Color(0x1A000000);
   static const gradientStart = Color(0xFF1A56DB);
   static const gradientEnd = Color(0xFF00C9A7);
   static const chatUserBubble = Color(0xFF1A56DB);
-  static const chatAiBubble = Color(0xFFF1F5F9);
   static const scanOverlay = Color(0x801A56DB);
+
+  // Light palette (raw values)
+  static const _lightBackground = Color(0xFFF8FAFC);
+  static const _lightSurface = Color(0xFFFFFFFF);
+  static const _lightTextPrimary = Color(0xFF1E293B);
+  static const _lightTextSecondary = Color(0xFF64748B);
+  static const _lightTextTertiary = Color(0xFF94A3B8);
+  static const _lightDivider = Color(0xFFE2E8F0);
+  static const _lightCardShadow = Color(0x1A000000);
+  static const _lightChatAiBubble = Color(0xFFF1F5F9);
+
+  // Dark palette (raw values)
+  static const _darkBackground = Color(0xFF0F172A);
+  static const _darkSurface = Color(0xFF1E293B);
+  static const _darkTextPrimary = Color(0xFFE2E8F0);
+  static const _darkTextSecondary = Color(0xFF94A3B8);
+  static const _darkTextTertiary = Color(0xFF64748B);
+  static const _darkDivider = Color(0xFF334155);
+  static const _darkCardShadow = Color(0x40000000);
+  static const _darkChatAiBubble = Color(0xFF1E293B);
+
+  // Mutable references — flipped at runtime via applyMode.
+  static Color background = _lightBackground;
+  static Color surface = _lightSurface;
+  static Color textPrimary = _lightTextPrimary;
+  static Color textSecondary = _lightTextSecondary;
+  static Color textTertiary = _lightTextTertiary;
+  static Color divider = _lightDivider;
+  static Color cardShadow = _lightCardShadow;
+  static Color chatAiBubble = _lightChatAiBubble;
+  static bool isDark = false;
+
+  static void applyMode(bool dark) {
+    isDark = dark;
+    if (dark) {
+      background = _darkBackground;
+      surface = _darkSurface;
+      textPrimary = _darkTextPrimary;
+      textSecondary = _darkTextSecondary;
+      textTertiary = _darkTextTertiary;
+      divider = _darkDivider;
+      cardShadow = _darkCardShadow;
+      chatAiBubble = _darkChatAiBubble;
+    } else {
+      background = _lightBackground;
+      surface = _lightSurface;
+      textPrimary = _lightTextPrimary;
+      textSecondary = _lightTextSecondary;
+      textTertiary = _lightTextTertiary;
+      divider = _lightDivider;
+      cardShadow = _lightCardShadow;
+      chatAiBubble = _lightChatAiBubble;
+    }
+  }
 }
 
 class AppTheme {
-  static ThemeData get lightTheme {
+  static ThemeData get theme {
+    final dark = AppColors.isDark;
     return ThemeData(
       useMaterial3: true,
-      brightness: Brightness.light,
-      colorScheme: const ColorScheme.light(
-        primary: AppColors.primary,
-        onPrimary: Colors.white,
-        secondary: AppColors.accent,
-        onSecondary: Colors.white,
-        surface: AppColors.surface,
-        onSurface: AppColors.textPrimary,
-        error: AppColors.error,
-        onError: Colors.white,
-        background: AppColors.background,
-        onBackground: AppColors.textPrimary,
-      ),
+      brightness: dark ? Brightness.dark : Brightness.light,
+      colorScheme: dark
+          ? ColorScheme.dark(
+              primary: AppColors.primaryLight,
+              onPrimary: Colors.white,
+              secondary: AppColors.accent,
+              onSecondary: Colors.white,
+              surface: AppColors.surface,
+              onSurface: AppColors.textPrimary,
+              error: AppColors.error,
+              onError: Colors.white,
+              background: AppColors.background,
+              onBackground: AppColors.textPrimary,
+            )
+          : ColorScheme.light(
+              primary: AppColors.primary,
+              onPrimary: Colors.white,
+              secondary: AppColors.accent,
+              onSecondary: Colors.white,
+              surface: AppColors.surface,
+              onSurface: AppColors.textPrimary,
+              error: AppColors.error,
+              onError: Colors.white,
+              background: AppColors.background,
+              onBackground: AppColors.textPrimary,
+            ),
       scaffoldBackgroundColor: AppColors.background,
       textTheme: GoogleFonts.notoSansScTextTheme().copyWith(
         displayLarge: GoogleFonts.notoSansSc(
@@ -72,7 +133,8 @@ class AppTheme {
         centerTitle: true,
         backgroundColor: AppColors.surface,
         foregroundColor: AppColors.textPrimary,
-        systemOverlayStyle: SystemUiOverlayStyle.dark,
+        systemOverlayStyle:
+            dark ? SystemUiOverlayStyle.light : SystemUiOverlayStyle.dark,
         titleTextStyle: GoogleFonts.notoSansSc(
           fontSize: 18, fontWeight: FontWeight.w600, color: AppColors.textPrimary,
         ),
@@ -148,7 +210,7 @@ class AppTheme {
         foregroundColor: Colors.white,
         elevation: 4,
       ),
-      bottomNavigationBarTheme: const BottomNavigationBarThemeData(
+      bottomNavigationBarTheme: BottomNavigationBarThemeData(
         backgroundColor: AppColors.surface,
         selectedItemColor: AppColors.primary,
         unselectedItemColor: AppColors.textTertiary,
@@ -163,7 +225,7 @@ class AppTheme {
           borderRadius: BorderRadius.circular(8),
         ),
       ),
-      dividerTheme: const DividerThemeData(
+      dividerTheme: DividerThemeData(
         color: AppColors.divider,
         thickness: 1,
         space: 1,
@@ -181,33 +243,22 @@ class AppTheme {
       ),
     );
   }
-
-  static ThemeData get darkTheme {
-    return lightTheme.copyWith(
-      brightness: Brightness.dark,
-      colorScheme: const ColorScheme.dark(
-        primary: AppColors.primaryLight,
-        onPrimary: Colors.white,
-        secondary: AppColors.accent,
-        onSecondary: Colors.white,
-        surface: Color(0xFF1E293B),
-        onSurface: Colors.white,
-        error: AppColors.error,
-        onError: Colors.white,
-        background: Color(0xFF0F172A),
-        onBackground: Colors.white,
-      ),
-      scaffoldBackgroundColor: const Color(0xFF0F172A),
-    );
-  }
 }
 
 class AppGradients {
-  static const primary = LinearGradient(
-    colors: [AppColors.gradientStart, AppColors.gradientEnd],
-    begin: Alignment.topLeft,
-    end: Alignment.bottomRight,
-  );
+  // Light: bright brand blue → teal. Dark: deeper, more subdued.
+  static const _lightStart = Color(0xFF1A56DB);
+  static const _lightEnd = Color(0xFF00C9A7);
+  static const _darkStart = Color(0xFF1E3A8A);
+  static const _darkEnd = Color(0xFF0F766E);
+
+  static LinearGradient get primary => LinearGradient(
+        colors: AppColors.isDark
+            ? const [_darkStart, _darkEnd]
+            : const [_lightStart, _lightEnd],
+        begin: Alignment.topLeft,
+        end: Alignment.bottomRight,
+      );
 
   static const card = LinearGradient(
     colors: [Color(0xFF1A56DB), Color(0xFF2563EB)],