@override
  Widget build(BuildContext context) {
    return Scaffold(
      body: IndexedStack(
        index: 0,
        children: <Widget>[
          Container(
            width: MediaQuery.of(context).size.width,
            height: MediaQuery.of(context).size.height,
            color: Colors.red,
          ),
          Positioned(
            top: 350,
            left: 80,
            child: Container(
              width: 250.0,
              height: 250.0,
              color: Colors.amber,
            ),
          ),
          Positioned(
            top: 450,
            left: 90,
            child: Text(
              'Inside stack widget', style: TextStyle(
                color: Colors.black,
                fontSize: 25.0,
                fontWeight: FontWeight.bold
              ),
            ),
          )
        ],
      ),
    );
  }