import 'dart:math';
import 'package:flutter/material.dart';

final Color darkBlue = Color.fromARGB(255, 18, 32, 47);

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(scaffoldBackgroundColor: darkBlue),
      debugShowCheckedModeBanner: false,
      home: Scaffold(
        body: Center(
          child: MyWidget(),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Transform.rotate(
        angle: 0,
        child: Scaffold(
            appBar: AppBar(
              title: Text('Hello, again'),
            ),
            body: Stack(
//         fit: StackFit.expand,
                children: [
                  Container(
                      height: 800,
                      width: 800,
                      child: Image.network(
                        'https://wallpaperplay.com/walls/full/e/5/3/13586.jpg',
                        fit: BoxFit.cover,
                      )),
                  _getOverlay()
                ])));
  }

  Widget _getOverlay() {
    return ColorFiltered(
      colorFilter: ColorFilter.mode(Colors.black54, BlendMode.srcOut),
      child: Stack(
        children: [
          Container(
            decoration: BoxDecoration(
              color: Colors.transparent,
            ),
            child: Align(
              alignment: Alignment(-0.3, -0.8),
              child: Container(
                margin: const EdgeInsets.only(right: 4, bottom: 4),
                height: 80,
                width: 160,
                decoration: BoxDecoration(
                  color: Colors.black, // Color does not matter but should not be transparent
                  borderRadius: BorderRadius.circular(40),
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}