CODE EXAMPLE FOR DART

flutter animatedcontainer

AnimatedContainer(
          width: MediaQuery.of(context).size.width, //change to see the change - super cool
          alignment: Alignment.bottomCenter,        //align to i.e topCenter to see the awesome transition
          height: MediaQuery.of(context).size.height,
          duration: Duration(milliseconds: 100),
          padding: EdgeInsets.fromLTRB(15, 10, 15, 5),
          decoration: BoxDecoration(
              gradient: LinearGradient(
            begin: Alignment.topRight,
            end: Alignment.bottomLeft,
            colors: [Colors.grey, Colors.white],
          )),