Custom_transition.dart

transitionBuilder: (Widget child, Animation<double> animation) {
            final scaleTween = TweenSequence([
              TweenSequenceItem(tween: Tween(begin: 1.0, end: 1.2), weight: 1),
              TweenSequenceItem(tween: Tween(begin: 1.2, end: 1.0), weight: 1),
            ]);
            return ScaleTransition(
              scale: scaleTween.animate(animation),
              child: child,
            );
          }