I have a simple CSS hover gallery which displays a photo when a user hovers on some text. It works fine as a stand-alone html, but when added to a wordpress page it does not works properly - the width of the image is limited to the with of the text which is a list element.
We’d need to see a link … but there’s no reason it can’t work in WP per se. There may be some other styles / scripts on the WP page that are interfering.
In the past, I would have recommended that you install Firebug for Firefox, as it’s an excellent inspector tool … but I feel that the inspect tools in Chrome have caught up. (The native inspection tools in firefox are pretty new and not very good.)