box_shadow.dart

new Container(
        width: 100,
        height: 100,
        decoration: new BoxDecoration(
    boxShadow: [
      BoxShadow(
        color: Colors.grey.withOpacity(.5),
        blurRadius: 20.0, // soften the shadow
        spreadRadius: 0.0, //extend the shadow
        offset: Offset(
          5.0, // Move to right 10  horizontally
          5.0, // Move to bottom 10 Vertically
        ),
      )
    ],
),