update theme

lib/features/cart/presentation/widgets/checkout_submit_button.dart

@@ -42,6 +42,8 @@ class CheckoutSubmitButton extends HookConsumerWidget {
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
+    final colorScheme = Theme.of(context).colorScheme;
+
     return Container(
       width: double.infinity,
       padding: const EdgeInsets.symmetric(horizontal: AppSpacing.md),
@@ -66,8 +68,8 @@ class CheckoutSubmitButton extends HookConsumerWidget {
         style: ElevatedButton.styleFrom(
           backgroundColor: ignorePricingRule
               ? AppColors.warning
-              : AppColors.primaryBlue,
-          foregroundColor: Colors.white,
+              : colorScheme.primary,
+          foregroundColor: colorScheme.surface,
           padding: const EdgeInsets.symmetric(vertical: 16),
           elevation: 0,
           shape: RoundedRectangleBorder(