在main函数加入：

import 'package:flutter/services.dart';

void main() {
  runApp(MyApp());

  // 沉浸式状态栏
  SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(
    systemNavigationBarColor: Colors.transparent,
    systemNavigationBarIconBrightness: Brightness.dark,
  ));
}