/*buttons */
var nav01off = new Image(); nav01off.src = "images/nav/01-off.gif";
var nav01on = new Image(); nav01on.src = "images/nav/01-on.gif";
var nav02off = new Image(); nav02off.src = "images/nav/02-off.gif";
var nav02on = new Image(); nav02on.src = "images/nav/02-on.gif";
var nav03off = new Image(); nav03off.src = "images/nav/03-off.gif";
var nav03on = new Image(); nav03on.src = "images/nav/03-on.gif";
var nav04off = new Image(); nav04off.src = "images/nav/04-off.gif";
var nav04on = new Image(); nav04on.src = "images/nav/04-on.gif";
var nav05off = new Image(); nav05off.src = "images/nav/05-off.gif";
var nav05on = new Image(); nav05on.src = "images/nav/05-on.gif";
var nav06off = new Image(); nav06off.src = "images/nav/06-off.gif";
var nav06on = new Image(); nav06on.src = "images/nav/06-on.gif";

function turnOn(imgName) {
  if (document.images) 
    document[imgName + "-roll"].src = eval(imgName + 'on.src');
}
function turnOff(imgName) {
  if (document.images)
    document[imgName + "-roll"].src = eval(imgName + 'off.src');
}