Test the DHTML pop-up link.

Test the DHTML pop-up link.

I won't address any issues regarding merit of using CSS method vis-a-vis Javascript or any Javascript issues, since I'm a novice, except to say that:
Use type="text/javascript" instead of language="JavaScript" - (you should also use type="text/css").

I have made some HTML, CSS and Javascript changes - see the source (the popup was messed up because you used unnecessary width:100%;). I have only changed the obvious and what I felt was necessary.

As an explanation of the meat (positioning of the popup), note the following:

I have changed the "showpopup" DIV to be classed and I set the Position Property to Relative.
I have changed the "ratePopup" DIV to an ID Attribute, since it will be the one to hide/show and I set the Position Property to Absolute.
This permits positioning of "ratePopup" with TOP/LEFT relative to "showpopup" and it won't take up any real estate since it is out of the normal flow.
This is also useful if you plan to use other popups where you will then want to be able to position them relative to their own wrapper. To demonstrate this, I have added a second popup (whatever) to demonstrate.