style.css

[class^="icon-"]{
    display: inline-block;
    background: url('../img/icons/icons.png') no-repeat;
    width: 64px;
    height: 51px;
    overflow: hidden;
    zoom:0.5;
    -moz-transform:scale(0.5);
    -moz-transform-origin: 0 0;
}

.icon-huge{
    zoom:1;
    -moz-transform:scale(1);
    -moz-transform-origin: 0 0;
}

.icon-big{
    zoom:0.60;
    -moz-transform:scale(0.60);
    -moz-transform-origin: 0 0;
}

.icon-small{
    zoom:0.29;
    -moz-transform:scale(0.29);
    -moz-transform-origin: 0 0;
}