var amount=20;
var showed=1;

function hide()  {
			button[0].style.visibility='hidden';
			button[1].style.visibility='hidden';
			button[2].style.visibility='hidden';
			button[3].style.visibility='hidden';
}

function show()  { 
button[0].style.visibility='visible';
button[1].style.visibility='visible';
button[2].style.visibility='visible';
button[3].style.visibility='visible';
}

function alphaChange(op) {
	if (op <= 100 && op >= 0) {
		button[0].style.opacity=op/100;
		button[1].style.opacity=op/100;
		button[2].style.opacity=op/100;
		button[3].style.opacity=op/100;
		setTimeout("alphaChange(" + (op+amount) + ")", 10);
	}
	else {
		if (op<0) showed=0;
		if (op>100) showed=1;
		if (amount < 0 && op<0) {
		}
	}
}