function Hide(id) {
    obj = document.getElementsByTagName("div");
    if (obj[id].style.visibility == 'visible'){
    obj[id].style.visibility = 'hidden';
    }

}



function Show(id) {
    obj = document.getElementsByTagName("div");
    if (obj[id].style.visibility != 'visible'){
    obj[id].style.visibility = 'visible';
    }

}



function change(id,klasse) {
document.getElementById(id).className = klasse;
}