Thank you so much!! That worked out great. I had to modify it a little, and I ended up sticking it all in one function, but here is the final code:
I used the getElementsByTagName because there are several of these popups in a dynamic table and I needed to get the right one. Other than that I don't think I changed much.
Here is the relevant css information.
Thank you again.
Now on the next iteration I'll probably have to size the popup window to fit the table in it.