Styling input file Firefox?

Question

Possible Duplicate:
Styling an input type=“file” button

I tried to style an input file.

It works great with Chrome and Safari but not with Firefox.

CSS :

input[type="file"] {
   position: absolute; 
   padding: 0px; 
   width: 100%!important; 
   height: 220px; 
   background: #000; 
   top: 0;
   z-index: 3000;
}

HTML :

<input type="file" multiple="multiple" name="uploadfile[]" />

Chrome :

Firefox :

Do you have a solution for Firefox, please ?

Thanks