function visintrobilde() {
	var introbilde = document.getElementById("introbilde");
	if (introbilde) {
		var randomnumber = Math.floor(Math.random()*6) // one more than top of array.
		var imageList = new Array(5)
		imageList[0] = "random1.jpg"
		imageList[1] = "random2.jpg"
		imageList[2] = "random3.jpg"
		imageList[3] = "random4.jpg"
		imageList[4] = "random5.jpg"
		imageList[5] = "random6.jpg"
		var url = "../images/" + imageList[randomnumber]
		introbilde.src=url;
	}
}
function preloadBilder() {
	var preloadbilde1 = new Image();
	var preloadbilde2 = new Image();
	preloadbilde1.src="gfx/flagg_engelsk_on";
	preloadbilde2.src="gfx/flagg_norsk_on.gif";
}
function on (caller) {
	var img = caller;
	url = img.src.substring(0,img.src.length-4) + "_on." + img.src.substring(img.src.length-3)
	caller.src=url;
}
function off (caller) {
	var img = caller;
	url = img.src.substring(0,img.src.length-7) + "." + img.src.substring(img.src.length-3)
	caller.src=url;
}