css text size issues on firefox

Hi

I'd like to have 2 different css strings for the shown issues on image if possible.
Note: my aero style from the windows system is disabled for personal reasons,
so backgrounds that look like aero are css based.


& another strange issue with this little portion:
menu { color: #000 !important;
border: 1px solid #ECEDEB !important;
font-size: 14px !important;
font-family: Times New Roman !important; }

menu:hover { background-color: #CDE2FC !important;
color: #000 !important;
border: 1px solid #78AEE4 !important;
font-size: 14px !important;
font-family: Times New Roman !important; }


I tried to set the color to invisible in this line:
border: 1px solid #ECEDEB !important;
and it still makes menu items move during hovering process..
so i changed it to grey & it fixed the issue, the menu bar doesn't move anymore,
but in this sad tweak, if i change the persona skin, the grey bars appear..
& all i want is to make sure hovering or not, the menu items don't move:
file|edit etc etc

hopefully someone will answer, but wanted to mention that for my firefox css issues I usually post here:
Firefox CSS: The UnixPorn of Firefox