function naviUp(num) {
    e = document.getElementById("li"+num);
    e.style.backgroundPosition = "left top";
    e.style.top = "-5px";
    e.style.height = "31px";
}
function naviDown(num) {
    e = document.getElementById("li"+num);
    e.style.backgroundPosition = "left bottom";
    e.style.top = "0";
    e.style.height = "26px";
}