HTML and CSS Reference
In-Depth Information
Light box scripts use a semi-opaque PNG image to darken the background,
while bringing a new element, usually a window-like
<div>
to the
foreground. The PNG overlay and the
<div>
both utilize
z-index
to
ensure those two elements are above all others on the page.
DROP-DOWN MENUS
Drop down menus such as Brainjar's classic Revenge of the Menu Bar use
z-index
to ensure the menu buttons and their drop-downs are at the top of
the stack.
