update theme

lib/features/cart/presentation/pages/checkout_page.dart

@@ -42,6 +42,8 @@ class CheckoutPage extends HookConsumerWidget {
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
+    final colorScheme = Theme.of(context).colorScheme;
+
     // Form key for validation
     final formKey = useMemoized(() => GlobalKey<FormState>());
 
@@ -102,22 +104,22 @@ class CheckoutPage extends HookConsumerWidget {
     final total = subtotal - memberDiscount + shipping;
 
     return Scaffold(
-      backgroundColor: const Color(0xFFF4F6F8),
+      backgroundColor: colorScheme.surfaceContainerLowest,
       appBar: AppBar(
-        backgroundColor: Colors.white,
+        backgroundColor: colorScheme.surface,
         elevation: 0,
         leading: IconButton(
-          icon: const FaIcon(
+          icon: FaIcon(
             FontAwesomeIcons.arrowLeft,
-            color: Colors.black,
+            color: colorScheme.onSurface,
             size: 20,
           ),
           onPressed: () => context.pop(),
         ),
-        title: const Text(
+        title: Text(
           'Thanh toán',
           style: TextStyle(
-            color: Colors.black,
+            color: colorScheme.onSurface,
             fontSize: 18,
             fontWeight: FontWeight.bold,
           ),
@@ -165,11 +167,11 @@ class CheckoutPage extends HookConsumerWidget {
                     margin: const EdgeInsets.symmetric(horizontal: AppSpacing.md),
                     padding: const EdgeInsets.all(AppSpacing.md),
                     decoration: BoxDecoration(
-                      color: Colors.white,
+                      color: colorScheme.surface,
                       borderRadius: BorderRadius.circular(AppRadius.card),
                       boxShadow: [
                         BoxShadow(
-                          color: Colors.black.withValues(alpha: 0.05),
+                          color: colorScheme.onSurface.withValues(alpha: 0.05),
                           blurRadius: 8,
                           offset: const Offset(0, 2),
                         ),
@@ -183,11 +185,11 @@ class CheckoutPage extends HookConsumerWidget {
                     margin: const EdgeInsets.symmetric(horizontal: AppSpacing.md),
                     padding: const EdgeInsets.all(AppSpacing.md),
                     decoration: BoxDecoration(
-                      color: Colors.white,
+                      color: colorScheme.surface,
                       borderRadius: BorderRadius.circular(AppRadius.card),
                       boxShadow: [
                         BoxShadow(
-                          color: Colors.black.withValues(alpha: 0.05),
+                          color: colorScheme.onSurface.withValues(alpha: 0.05),
                           blurRadius: 8,
                           offset: const Offset(0, 2),
                         ),
@@ -203,9 +205,9 @@ class CheckoutPage extends HookConsumerWidget {
                         const SizedBox(height: 12),
                         Text(
                           'Không thể tải phương thức thanh toán',
-                          style: const TextStyle(
+                          style: TextStyle(
                             fontSize: 14,
-                            color: AppColors.grey500,
+                            color: colorScheme.onSurfaceVariant,
                           ),
                           textAlign: TextAlign.center,
                         ),
@@ -225,7 +227,7 @@ class CheckoutPage extends HookConsumerWidget {
                 const SizedBox(height: AppSpacing.md),
 
               // Discount Code Section
-              _buildDiscountCodeSection(),
+              _buildDiscountCodeSection(context),
 
               const SizedBox(height: AppSpacing.md),
 
@@ -263,13 +265,13 @@ class CheckoutPage extends HookConsumerWidget {
                       },
                       activeColor: AppColors.warning,
                     ),
-                    const Expanded(
+                    Expanded(
                       child: Text(
                         'Yêu cầu hợp đồng',
                         style: TextStyle(
                           fontSize: 15,
                           fontWeight: FontWeight.w600,
-                          color: Color(0xFF212121),
+                          color: colorScheme.onSurface,
                         ),
                       ),
                     ),
@@ -281,20 +283,20 @@ class CheckoutPage extends HookConsumerWidget {
               const SizedBox(height: AppSpacing.md),
 
               // Terms and Conditions
-              const Padding(
-                padding: EdgeInsets.symmetric(horizontal: AppSpacing.md),
+              Padding(
+                padding: const EdgeInsets.symmetric(horizontal: AppSpacing.md),
                 child: Text.rich(
                   TextSpan(
                     text: 'Bằng cách đặt hàng, bạn đồng ý với ',
                     style: TextStyle(
                       fontSize: 14,
-                      color: Color(0xFF6B7280),
+                      color: colorScheme.onSurfaceVariant,
                     ),
                     children: [
                       TextSpan(
                         text: 'Điều khoản & Điều kiện',
                         style: TextStyle(
-                          color: AppColors.primaryBlue,
+                          color: colorScheme.primary,
                           decoration: TextDecoration.underline,
                         ),
                       ),
@@ -328,16 +330,18 @@ class CheckoutPage extends HookConsumerWidget {
   }
 
   /// Build Discount Code Section (Card 4 from HTML)
-  Widget _buildDiscountCodeSection() {
+  Widget _buildDiscountCodeSection(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+
     return Container(
       margin: const EdgeInsets.symmetric(horizontal: AppSpacing.md),
       padding: const EdgeInsets.all(AppSpacing.md),
       decoration: BoxDecoration(
-        color: Colors.white,
+        color: colorScheme.surface,
         borderRadius: BorderRadius.circular(AppRadius.card),
         boxShadow: [
           BoxShadow(
-            color: Colors.black.withValues(alpha: 0.05),
+            color: colorScheme.onSurface.withValues(alpha: 0.05),
             blurRadius: 8,
             offset: const Offset(0, 2),
           ),
@@ -351,16 +355,16 @@ class CheckoutPage extends HookConsumerWidget {
             children: [
               Icon(
                 FontAwesomeIcons.ticket,
-                color: AppColors.primaryBlue,
+                color: colorScheme.primary,
                 size: 20,
               ),
               const SizedBox(width: 8),
-              const Text(
+              Text(
                 'Mã giảm giá',
                 style: TextStyle(
                   fontSize: 16,
                   fontWeight: FontWeight.bold,
-                  color: Color(0xFF212121),
+                  color: colorScheme.onSurface,
                 ),
               ),
             ],
@@ -377,16 +381,16 @@ class CheckoutPage extends HookConsumerWidget {
                     hintText: 'Nhập mã giảm giá',
                     border: OutlineInputBorder(
                       borderRadius: BorderRadius.circular(8),
-                      borderSide: const BorderSide(color: Color(0xFFD1D5DB)),
+                      borderSide: BorderSide(color: colorScheme.outlineVariant),
                     ),
                     enabledBorder: OutlineInputBorder(
                       borderRadius: BorderRadius.circular(8),
-                      borderSide: const BorderSide(color: Color(0xFFD1D5DB)),
+                      borderSide: BorderSide(color: colorScheme.outlineVariant),
                     ),
                     focusedBorder: OutlineInputBorder(
                       borderRadius: BorderRadius.circular(8),
-                      borderSide: const BorderSide(
-                        color: AppColors.primaryBlue,
+                      borderSide: BorderSide(
+                        color: colorScheme.primary,
                         width: 2,
                       ),
                     ),
@@ -403,7 +407,7 @@ class CheckoutPage extends HookConsumerWidget {
                   // TODO: Apply discount code
                 },
                 style: ElevatedButton.styleFrom(
-                  backgroundColor: AppColors.primaryBlue,
+                  backgroundColor: colorScheme.primary,
                   padding: const EdgeInsets.symmetric(
                     horizontal: 24,
                     vertical: 12,
@@ -413,10 +417,10 @@ class CheckoutPage extends HookConsumerWidget {
                   ),
                   elevation: 0,
                 ),
-                child: const Text(
+                child: Text(
                   'Áp dụng',
                   style: TextStyle(
-                    color: Colors.white,
+                    color: colorScheme.onPrimary,
                     fontWeight: FontWeight.w600,
                   ),
                 ),
@@ -436,18 +440,18 @@ class CheckoutPage extends HookConsumerWidget {
             ),
             child: Row(
               children: [
-                Icon(
+                const Icon(
                   FontAwesomeIcons.circleCheck,
                   color: AppColors.success,
                   size: 18,
                 ),
                 const SizedBox(width: 8),
-                const Expanded(
+                Expanded(
                   child: Text(
                     'Bạn được giảm 15% (hạng Diamond)',
                     style: TextStyle(
                       fontSize: 14,
-                      color: Color(0xFF166534),
+                      color: const Color(0xFF166534),
                       fontWeight: FontWeight.w500,
                     ),
                   ),