function viewMenu(nummer) {
document.all.box1.style.visibility = "hidden";
document.all.box2.style.visibility = "hidden";
document.all.box3.style.visibility = "hidden";
document.all.box4.style.visibility = "hidden";
document.all.box5.style.visibility = "hidden";
document.all.menu1.src = "images/b1.jpg";
document.all.menu2.src = "images/b2.jpg";
document.all.menu3.src = "images/b3.jpg";
document.all.menu4.src = "images/b4.jpg";
document.all.menu5.src = "images/b5.jpg";

if (nummer == "1") {
document.all.box1.style.visibility = "visible";
document.all.menu1.src = "images/b1o.jpg";
}
if (nummer == "2") {
document.all.box2.style.visibility = "visible";
document.all.menu2.src = "images/b2o.jpg";
}
if (nummer == "3") {
document.all.box3.style.visibility = "visible";
document.all.menu3.src = "images/b3o.jpg";
}
if (nummer == "4") {
document.all.box4.style.visibility = "visible";
document.all.menu4.src = "images/b4o.jpg";
}
if (nummer == "5") {
document.all.box5.style.visibility = "visible";
document.all.menu5.src = "images/b5o.jpg";
}

}