Flutter positioning and button sizing

    return new MaterialApp(
      title: "Test",
      home: new Scaffold(
        body: new Center(
          child: new Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              new Container(
                padding: new EdgeInsets.fromLTRB(0.0, 0.0, 0.0, 30.0),
                child: new Text("Please login to continue"),
              ),
              new Container(
                padding: new EdgeInsets.fromLTRB(0.0, 0.0, 0.0, 30.0),
                child: new FlatButton(
                  child: new Container(
                    child: new Center(
                      child: new Text("Google"),
                    ),
                    width: 150.0,
                    height: 40.0
                  ),
                  color: Colors.red,
                  onPressed: () {_googleLogin();},
                )
              ),
              new Container(
                padding: new EdgeInsets.fromLTRB(0.0, 0.0, 0.0, 30.0),
                child: new FlatButton(
                  child: new Container(
                    child: new Center(
                      child: new Text("Facebook"),
                    ),
                    width: 150.0,
                    height: 40.0
                  ),
                  color: Colors.blue,
                  onPressed: () {_facebookLogin();},
                )
              )
            ],
          )
        )
      )
    );