On a simple web page, where there are no objects overlapping, EverWeb will take care of z-index and the user will be none the wiser. Where there are elements which appear on hover or click, a little more thought may be required.
Some elements which appear on click are actually there all the time - even although they can’t be seen. Since they require a higher z-index than the surrounding content, this will effect any dynamic content within these elements which they overlap. The most common of the elements effected is hyperlinks - text or image.
Here's an example of why it's a good idea to learn the basics of stacking order...
The image below left shows the icon navigation widget in the opened position. Since the area occupied by the navigation button extends right across the green rectangle, any links placed in that area with a lower z-index will not work.
The image below right shows an image link placed in the dead area. For this hyperlink to work, the icon should be brought to the front AFTER the navigation.