Perhaps this note will save another member a spot of frustration.
I tried to login from my mobile phone, but the AMD ad banner kept popping over the login dialog no matter how I tried to scroll away from it.
Here's a workaround. The problem occurred holding the phone in landscape aspect, which is convenient to using the keyboard. If I hold it in portrait aspect, the pop ups don't overlap!
Even so the site maintainer might want to switch the order of popovers so the login dialog gets final focus.
Regards, hardmath