var curStep = 1;
var steps = new Array();
function imagegallery(num) {
steps = document.getElementById("gallery_nav").getElementsByTagName("li");
	if (num != curStep) {
		elem = document.getElementById("gallery" + num);
		prevElem = document.getElementById("gallery" + curStep);
		elem.style.display = "block";
		prevElem.style.display = "none";
		steps[curStep-1].className = "";
		steps[num-1].className = "active";
		curStep = num;
	}
}