function menu() {
	y = (window.pageYOffset >= document.documentElement.scrollTop) ? window.pageYOffset : document.documentElement.scrollTop;
	menuvar = document.getElementById("menubar");
	if (y >= 100 ) {
		menuvar.style.position="fixed";
		menuvar.style.top="0";
		menuvar.style.bottom="";
	} else {
		menuvar.style.position="absolute";
		menuvar.style.bottom="0";
		menuvar.style.top="";
	}
}

function domenu() {
	setInterval("menu()", 1);
}

function showdiv(id) {
	var x = document.getElementById(id);
	x.style.display = (x.style.display != 'block' ? 'block' : 'none' );
}