Animation in Vertical

Vaadin 6 / 7 / 8
1

Hi,

I am using Animator add-on and I need collapse a panel. My code is:

Animator.animate(panel, new Css().height("0px")).delay(50).duration(2000);

The panel is collapsed but without animation! If I use other transformations like translate, scale the animation work normally.
What is the problem?

Thanks