function checkb(x){if(x.checked)x.checked=false;else x.checked=true;}

onload = initAll;

function initAll() {
	document.getElementById("hidden-1").style.clip = "rect(auto, auto, "+0+"px, auto)";
	document.getElementById("hidden-2").style.clip = "rect(auto, auto, "+0+"px, auto)";
	document.getElementById("hidden-bg").style.clip = "rect(auto, auto, "+0+"px, auto)";
}

var cut = 0;
var time = 10;
var step = 10;
var time_down, time_out;
var menu_on = 0;

function roll_down() {
	if(window.time_down) {
		clearInterval(time_down);
		clearInterval(time_out);
	}
		time_down = setInterval("slide_down()",time);
}
function slide_down() {
	if (cut <= 144) {
		cut += step;
		document.getElementById("hidden-1").style.clip = "rect(auto auto "+cut+"px auto)";
		document.getElementById("hidden-2").style.clip = "rect(auto auto "+cut+"px auto)";
		document.getElementById("hidden-bg").style.clip = "rect(auto auto "+cut+"px auto)";
	} else {
		clearInterval(time_down);
		menu_on = 1;
		cut = 144;
	}
}

function roll_up() {
	if(window.time_out) {
		clearInterval(time_out);
		clearInterval(time_down);
	}
	time_out = setInterval("slide_up()",time);
}
function slide_up() {
	if (cut > 0) {
		cut -= step;
		if (cut < 0) {cut = 0;}
		document.getElementById("hidden-1").style.clip = "rect(auto auto "+cut+"px auto)";
		document.getElementById("hidden-2").style.clip = "rect(auto auto "+cut+"px auto)";
		document.getElementById("hidden-bg").style.clip = "rect(auto auto "+cut+"px auto)";
	} else {
		clearInterval(time_out);
		menu_on = 0;
	}
}