Need  help with a css hack for firefox browers.15.0.1 version

 

This is the screen shot that works in all browers accept firefox.

 

This screen shot is from firefox  as you can see the last Button is partly coved with the header called Our Packages

 

 

This is the css that place's the header called Out Packages under the row of buttons

 

#packagesheader {
    position: absolute;
    top: 163px;
    margin-top: 60px; /* 60px or 6em works in all browers but not firefox the header for Our packages does not  show correctly it covers the last Button called Contact Us */
    left: 448px;
}

 

have used this css  code in my page,s   w\idth:  padd\ing:    ,,,,,but dont no what to do for margin-top for firefox.