.it a span { 
    background-image:url(../images/flags/Italy.png);
    background-repeat:no-repeat;
    background-position:center; 
    -webkit-background-size: 16px 16px;
    -moz-background-size: 16px 16px;
    background-size: 16px 16px; 
}


.en a span { 
    background-image:url(../images/flags/Great_Britain.png);
    background-repeat:no-repeat;
    background-position:center; 
    -webkit-background-size: 16px 16px;
    -moz-background-size: 16px 16px;
    background-size: 16px 16px; 
}