Tilted Square, can you explain the clipping issue and how the z-index changes it? I was having the same problem with links not working in WordPress while they worked fine if I ran the page in Notepad++. I added the z-index you suggest above and my links now work.
In the situation above, is giving the div a higher z-index just moving it on top of the signup link? If you’re laying it on top of the link, how does that unblock the link?