#nav, #nav ul { /* all lists */
    padding: 0;
    margin: 0;
    list-style: none;
    line-height: 1;
}
#nav a {
    display: block;
    width: 175px;
}
#nav li { /* all list items */
    float: left;
   width: 175px; /* width needed or else Opera goes nuts */
}
#nav li ul { /* second-level lists */
    position: absolute;
    width: 175px;
    left: -999em; /* using left instead of display to hide menus because display: none isn't read by screen readers */
}
#nav li:hover, #nav li.sfhover {
    position: static;
}
#nav li:hover ul, #nav li.sfhover ul { /* lists nested under hovered list items */
    left: auto;
}