@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);

/* CHANGE FONT SIZE */

.tabbrowser-tabs *|tab {    
    font-size: 12px !important;
    min-width: 8px !important  
    }

/* CHANGE TAB HEIGHT */

tab>.tab-image-middle,tab,tabs{
    max-height:24px!important;
    /* CAN BE USED TO MOVE TABS UP/DOWN WITH POSITIVE/NEGATIVE VALUES... SET MAX-HEIGHT: 0PX 
    AND MARGIN-TOP: 24PX TO HIDE TABS*/
    margin-top:0px;
    padding-bottom:0px;
    }