CSS Inserts: h1-h6 and Firefox
 

I've put the following in the CSS inserts for h1-h6:

h1 { font-size: 2.25em; font-weight: bold; margin-bottom: 10px; }

The only thing different for h2-h6 is font-size. It works fine in IE, Chrome and Opera. Firefox only recognizes bottom margin. Any thoughts or ideas?

Recently upgraded all server software, so the only active plugin is Akismet. I have WP version 3.0.4 and Atahualpa 3.4.9.

I'm using an unpublished post for testing and previewing. Don't know if that matters.

Thanks

Brian