feat:更新颜色模块

lib/widgets/todo_widget.dart

@@ -5,7 +5,7 @@ import 'package:flutter/material.dart';
 import 'package:intl/intl.dart';
 
 // 统计卡片
-Widget buildTodoStatsCard(List<Todo> todos) {
+Widget buildTodoStatsCard(BuildContext context, List<Todo> todos) {
   int totalCount = todos.length;
 
   int activeCount = todos.where((todo) => !todo.isCompleted).length;
@@ -17,15 +17,15 @@ Widget buildTodoStatsCard(List<Todo> todos) {
       mainAxisAlignment: MainAxisAlignment.spaceAround,
       crossAxisAlignment: CrossAxisAlignment.center,
       children: [
-        _buildStatItem('总计', totalCount, Colors.blue),
-        _buildStatItem('待完成', activeCount, Colors.orange),
-        _buildStatItem('已完成', completedCount, Colors.green),
+        _buildStatItem(context, '总计', totalCount),
+        _buildStatItem(context, '待完成', activeCount),
+        _buildStatItem(context, '已完成', completedCount),
       ],
     ),
   );
 }
 
-Widget _buildStatItem(String label, int count, Color color) {
+Widget _buildStatItem(BuildContext context, String label, int count) {
   return Column(
     children: [
       Text(
@@ -33,7 +33,7 @@ Widget _buildStatItem(String label, int count, Color color) {
         style: TextStyle(
           fontSize: 24,
           fontWeight: FontWeight.bold,
-          color: color,
+          color: Theme.of(context).colorScheme.primary,
         ),
       ),
       const SizedBox(height: 4),