2403fd0680
The specs call for a 2 pixel gap between the panel and its menus, though we need to specify this as 4 pixels, since it's relative to the bottom of the icon/title, not the bottom of the panel (up until now, the point of the menu arrow was actually overlapping the menu's highlight underline). Also, move the gap specification into the CSS, since it makes more sense there. https://bugzilla.gnome.org/show_bug.cgi?id=655627