import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: Builder(
        builder: (context) => Scaffold(
          body: Column(
            children: [
              ConstrainedBox(
                constraints: BoxConstraints(
                  maxHeight: MediaQuery.of(context).size.width,
                ),
                child: Container(color: Colors.red.shade400),
              ),
              Expanded(
                child: Column(
                  children: [
                    Container(color: Colors.yellow.shade400, height: 100),
                    Flexible(
                      flex: 1,
                      child: Container(color: Colors.green.shade400),
                    ),
                    Container(color: Colors.blue.shade400, height: 100),
                  ],
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}