El efecto de Normal/Hover/Pressed en un Tile/Boton usando CSS

gistfile1.css

.tile-wrapper a
{
    border: 0px solid  red;
    margin: 0px;
    width: 128px;
    height:128px;
    display:block;
}

.tile-wrapper a:hover
{
    border: 0px solid  green;
    margin: 0px;
    width: 128px;
    height:128px;
    display:block;
}

.tile-wrapper a#id_Alerts
{
    background: url("../../Content/images/functionIcons/Active.png");
}

.tile-wrapper a#id_Alerts:hover
{
    background: url("../../Content/images/functionIcons/Hover.png");
}

.tile-wrapper a#id_Alerts:active
{
    background: url("../../Content/images/functionIcons/Pressed.png");
}