var isVisible = false; // is menu visible?

// toggle the visibility of the popup menu.
function toggleMenu( )
{
	setupPos( ); // make sure it is displayed in the right place
	
	var newClass = (isVisible) ? "popup_menu_hidden" : "popup_menu"; // assign new class to menu
	
	document.getElementById( "popupMenu" ).className = newClass;
	
	isVisible = !isVisible; // toggle checker
}

// setup the position of the popupmenu so it is displayed 
// in the right place even when the window is resized.
function setupPos( )
{
	var ctrl = document.getElementById( "popupMenu" );
	
	ctrl.style.left = document.body.offsetWidth+document.body.scrollLeft-157;
	ctrl.style.top = 121;
}

// hide popup menu
function hidePopupMenu( )
{
	document.getElementById( "popupMenu" ).className = "popup_menu_hidden";
	isVisible = false;
}