fix：按照shadcn_ui对着demo_shadcn对齐

lib/theme/app_theme.dart

@@ -2,7 +2,6 @@ import 'package:flutter/material.dart';
 
 import 'yanting_text.dart';
 import 'yanting_tokens.dart';
-import 'wise_tokens.dart';
 
 ThemeData buildAppTheme() {
   final scheme = ColorScheme.fromSeed(
@@ -29,13 +28,14 @@ ThemeData buildAppTheme() {
       elevation: 0,
       centerTitle: false,
       titleTextStyle: YantingText.sectionTitle,
+      surfaceTintColor: Colors.transparent,
     ),
     cardTheme: const CardThemeData(
       color: YantingColors.card,
       elevation: 0,
       margin: EdgeInsets.zero,
       shape: RoundedRectangleBorder(
-        borderRadius: BorderRadius.all(Radius.circular(WiseRadius.md)),
+        borderRadius: BorderRadius.all(Radius.circular(YantingRadius.xl)),
         side: BorderSide(color: YantingColors.border),
       ),
     ),
@@ -64,6 +64,16 @@ ThemeData buildAppTheme() {
         borderSide: const BorderSide(color: YantingColors.foreground),
       ),
     ),
+    snackBarTheme: SnackBarThemeData(
+      backgroundColor: YantingColors.foreground,
+      contentTextStyle: YantingText.body.copyWith(
+        color: YantingColors.background,
+      ),
+      behavior: SnackBarBehavior.floating,
+      shape: RoundedRectangleBorder(
+        borderRadius: BorderRadius.circular(YantingRadius.md),
+      ),
+    ),
     navigationBarTheme: NavigationBarThemeData(
       backgroundColor: YantingColors.background,
       indicatorColor: Colors.transparent,