input.dart

  final double animVal = shouldAnimate ? 0 : -50;
    return AnimatedPositioned(
      duration: Duration(milliseconds: 500),
      right: widget.suffix ? animVal : null,
      top: 0,
      left: widget.suffix ? null : animVal,
      bottom: 0,
      curve: curve,
      child: Container(
          width: 50,
          decoration: BoxDecoration(
            borderRadius: BorderRadius.horizontal(
              left: Radius.circular(5),
            ),
            color: color,
          ),
          child: icon),
    );
  }
}