Link background resizing incorrectly in Firefox

[djay]

I have a navigation bar with a simple hover effect of showing a lighter coloured background behind the links.

This background does not resize correctly in Firefox when zooming. The background area does resize, but is either smaller or larger than the height of the navigation bar, except at normal view which it matches the navigation bar. This isn't a problem with Opera or IE, where the resizing matches perfectly with the navigation bar.

So this seems to be a Firefox issue than my html? Is it fixable?

Thanks

[djay]

Fixed it by converting the link padding units from px to em's. I was using a mix of px and em, because I had decided to change over to ems half-way through, and had finally got around to changing them all over.

Not sure where is best to use px or em or which unit is better.