List extends beyond viewable window and won't scroll. Has anyone else experienced this behavior?

[lifeawesome]

No description provided.

[wenzhixin]

won't scroll? Is it because you set the overflow property like:

overflow: hidden;

[Roby73]

Hi all.
I have two div area, one over the other, and they have a fixed height. In the upper I put a select box with many items, near over the botton border. When I expand the control, the box of the select does to show the scroll bar on the right side of the window area, and I must scroll it, if I want to see the hidden items of the control!
This is my question! thanks.