Controls the vertical positioning of the origin point. By default the menu is absolutely positioning (top aligned) so Menu Vertical Offset specifies the distance from the top edge of the document (origin) to the menu. With vertical alignment set to "middle" or "bottom" the origin point moves to the middle of the document or to its bottom edge respectively. Then Menu Vertical Offset parameter is used to offset the menu down (positive value) or up (negative value) to the origin. The menu updates its position if browser window is resized.