There are several way to add shadow to a Container.

BoxDecoration with BoxShadow
Container( width: 200, height: 200, decoration: BoxDecoration( color: Colors.blue, borderRadius: BorderRadius.circular(16), boxShadow: [ BoxShadow( color: Colors.blueGrey, blurRadius: 4, offset: Offset(4, 8), // Shadow position ), ], ), )
PhysicalModel
PhysicalModel( color: Colors.blue, elevation: 8, shadowColor: Colors.blueGrey, borderRadius: BorderRadius.circular(16), child: Container(width: 200, height: 200), )
Material with shadowColor as a child of Container
Container( width: 200, height: 200, child: Material( borderRadius: BorderRadius.circular(16), elevation: 8, shadowColor: Colors.blueGrey, color: Colors.blue, child: Text('Container'), ), )