content: import 'package:flutter/material.dart';
  import 'package:rainbow_shortcut/shortcut_card.dart';
  
  void main() {
    runApp(const App());
  }
  
  class App extends StatefulWidget {
    const App({super.key});
  
    @override
    State<App> createState() => _AppState();
  }
  
  class _AppState extends State<App> {
    final _isLogoVisible = ValueNotifier(false);
  
    @override
    void dispose() {
      _isLogoVisible.dispose();
      super.dispose();
    }
  
    @override
    Widget build(BuildContext context) {
      return MaterialApp(
        debugShowCheckedModeBanner: false,
        home: Scaffold(
          backgroundColor: Colors.black,
          body: Stack(
            children: [
              Center(
                child: ShortcutCard(
                  onShortcut: () {
                    _isLogoVisible.value = true;
                  },
                ),
              ),
              Positioned(
                right: 15,
                bottom: -35,
                child: ValueListenableBuilder(
                  valueListenable: _isLogoVisible,
                  builder: (context, isLogoVisible, child) {
                    return AnimatedOpacity(
                      opacity: isLogoVisible ? 1 : 0,
                      duration: const Duration(milliseconds: 250),
                      curve: Curves.easeOut,
                      child: child,
                    );
                  },
                  child: FlutterLogo(
                    size: 130,
                    textColor: Colors.white.withOpacity(0.8),
                    style: FlutterLogoStyle.horizontal,
                  ),
                ),
              ),
            ],
          ),
        ),
      );
    }
  }
  