That worked - setting widths worked and setting "inline-block" on display property worked.
But now... when I hover over the one of the thumbnail images on this page, when the pop-up appears, it seems to rearrange the thumbnail images in the background - a little hard to see because the pop-up almost covers the thumbnails once it appears, but not completely.
Can you see what I'm referring to? Do the little thumbnails get rearranged because they are somehow not stationary? How can I fix this?