// JavaScript Document
img1_Off = new Image();
img1_Off.src = "http://www.macb.com/imgs/about-us.gif";
img1_On = new Image();
img1_On.src = "http://www.macb.com/imgs/about-us-over.gif";

img2_Off = new Image();
img2_Off.src = "http://www.macb.com/imgs/contract-vehicles.gif";
img2_On = new Image();
img2_On.src = "http://www.macb.com/imgs/contract-vehicles-over.gif";

img3_Off = new Image();
img3_Off.src = "http://www.macb.com/imgs/careers.gif";
img3_On = new Image();
img3_On.src = "http://www.macb.com/imgs/careers-over.gif";

img4_Off = new Image();
img4_Off.src = "http://www.macb.com/imgs/technical-services.gif";
img4_On = new Image();
img4_On.src = "http://www.macb.com/imgs/technical-services-over.gif";

img5_Off = new Image();
img5_Off.src = "http://www.macb.com/imgs/customers.gif";
img5_On = new Image();
img5_On.src = "http://www.macb.com/imgs/customers-over.gif";

//calculate years of age (input string: YYYY-MM-DD)
function age(){
    $year_diff  = date("Y") - 1979;
    return $year_diff;
  }

function swap(imgID)
{
	for (i=1; i<=5; i++)
	{
		id = eval("img" + i + "_Off.src");
		picID = "img" + i;
		document.getElementById(picID).src = id;
	}
	id = eval(imgID + "_On.src");
	document.getElementById(imgID).src = id;
}

function ChangeLayer(id)
{
	for (i=1; i<=5; i++)
	{
		document.getElementById(i).style.visibility='hidden';
	}
	document.getElementById(id).style.visibility='visible';
}

function changeDisplay(ElementID)
{
	if (document.getElementById(ElementID).style.display == "block")
	{	document.getElementById(ElementID).style.display = "none";	}
	else
	{	document.getElementById(ElementID).style.display = "block";	}
}