var oldId, oldBgColor;

function hiddenLayer(elem) {
document.getElementById(elem).style.visibility = 'hidden';}

function showLayer(elem) {
document.getElementById(elem).style.visibility = 'visible';}

function lightOn(elem) {
oldId = elem;
oldBgColor = document.getElementById(elem).style.background;
document.getElementById(elem).style.background = '#FBEF5F';}

function lightOff() {
document.getElementById(oldId).style.background = oldBgColor;}

function menuOn(elem) {
oldId = elem;
document.getElementById(elem).style.background = '#EEEEFF url("/image/menu1.gif") repeat-y';
}

function menuOff() {
document.getElementById(oldId).style.background = '#EEEEFF url("/image/menu0.gif") repeat-y';
}