var i=-30;
var d=0;
var intHide;
var intShow;
var speed=3;
function show_hide_menu()
{
if (d==0)
	{
	d=1;
	clearInterval(intHide);
	intShow=setInterval("show()",20);document.getElementById('change').innerHTML="Hide"
	}
else
	{
	d=0;
	clearInterval(intShow);
	intHide=setInterval("hide()",20);document.getElementById('change').innerHTML="Show"
	}
}
function show()
{
if (i<-5)
	{
	i=i+speed;
	document.getElementById('myMenu').style.top=i+"px";
	
	}
}
function hide()
{
if (i>-30)
	{
	i=i-speed;
	document.getElementById('myMenu').style.top=i+"px";
	}
}