function change_class(id) {
	document.getElementById(id).className=document.getElementById(id).className.replace(/-off/,"-on");
}

function restore_class(id){
	document.getElementById(id).className=document.getElementById(id).className.replace(/-on/,"-off");
}
function hide_menu()
{
	if (document.getElementById)
	{
		document.getElementById('menu_part').style.visibility="hidden";
		document.getElementById('menu_news').style.visibility="hidden";
		document.getElementById('menu_presse').style.visibility="hidden";
		document.getElementById('menu_point').style.visibility="hidden";
	}
}
function show_menu(id)
{
	hide_menu()
	if (document.getElementById)
		document.getElementById(id).style.visibility="visible";
	window.setTimeout("hide_menu()", 13000);
}