Specific image scaling

I am writing an application, the main screen of which will consist of two images – a poster and a panel with buttons at the bottom. I already made the bottom image overlap the top one by 10 pixels. To scale it, I use the fit property: BoxFit.fitWidth. Tell me, please, is it possible to make the widget fit only the upper left corner of the image and at the same time be able to scale?

It should be

how it shouldn't be

Home screen now

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: LayoutBuilder(
          builder: (context, constraints) {
            return Stack(
              children: [
                //Poster Section
                Align(
                  alignment: Alignment.topCenter,
                  child: Container(
                    width: constraints.maxWidth,
                    height: constraints.maxHeight * .92,
                    //color: Colors.blue,
                    child: Image.asset(
                        fit: BoxFit.fill, "images/Captain Clark.png"),
                  ),
                ),

                //Bottom bar section with buttons
                Align(
                  alignment: Alignment.bottomCenter,
                  child: Container(
                    width: constraints.maxWidth,
                    height: constraints.maxHeight * .08 + 8,
                    child: Stack(
                      fit: StackFit.expand,
                      alignment: Alignment.centerLeft,
                      children: [
                        //Panel background
                        Image.asset(fit: BoxFit.fitWidth, "images/Fon1-1.png"),
                        //Row with buttons
                        Row(