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import 'package:flutter/material.dart';

void main() {
  runApp(const PixelPage());
}

class PixelPage extends StatelessWidget {
  const PixelPage({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: NestedScrollView(
          headerSliverBuilder: (context, isScrolled),
          return [const SliverAppBar(
            pinned: true,
            expandedHeight: 200,
          )];
          body: Center(),
        ),
      ),
    );
  }
}