Advanced CSS menu

#access {
    width: 136px;
    top: 20px;
    position: absolute;
    padding: 0 0 0 644px;
    background-color: transparent;
}
#access .menu-header {
    width: 136px;
    margin: 0;
}
#access a {
    padding: 0;
    line-height: none;
}
.menu-header {
    background-color: #CCC;
    height: 112px;
    width: 136px;
}
ul#menu-top-navigation {
    list-style: none;
    margin: 0;
    padding: 0;
    position: relative;
}
ul#menu-top-navigation li a {
    background-position: left top;
    background-repeat: no-repeat;
    display: block;
    text-indent: -9000px;
    position: absolute;
}
ul#menu-top-navigation li a:hover{
    background-position: -136px 0;
}
ul#menu-top-navigation li.home a {
    background-image: url(images/home_button.gif);
    height: 22px;
    width: 136px;
    top: 0;
    left: 0;
}
ul#menu-top-navigation li.about a {
    background-image: url(images/aboutme_button.gif);
    height: 23px;
    width: 136px;
    top: 30px;
    left: 0;
}
ul#menu-top-navigation li.services a {
    background-image: url(images/services_button.gif);
    height: 20px;
    width: 136px;
    top: 61px;
    left: 0;
}ul#menu-top-navigation li.contact a {
    background-image: url(images/contactme_button.gif);
    height: 22px;
    width: 136px;
    top: 90px;
    left: 0;
}