function showExperienceSquare( itemID, showIsTrue)
{
	var anItem = document.getElementById('experienceSquare');

	if ( showIsTrue)
		anItem.style.backgroundImage = "url( images/experience/square" + itemID + ".jpg)";
	else
		anItem.style.visibility = "visible";

}

function advanceExperienceIntroduction()
{
	var anItem = document.getElementById('experienceIntroduction');
	
	// as a hack, we are using the div's z-index as a counter
	// to keep track of which page we are on
	if ( anItem != null)
	{
		anItem.style.zIndex++;
		if ( anItem.style.zIndex > 2)
		{
			anItem.style.zIndex = 0;
		}
		anItem.style.backgroundPosition = "left -" + anItem.style.zIndex * 249 + "px";
	}
}