function swapImage(id, src, txt) {
	$(id).style.backgroundImage = "url('" + src + "')";
	$('assortiment_tekst').style.display='block';
	$('assortiment_tekst_img').src='/kop.php?txt='+txt+'&type=assortiment';
}

function swapImageOut(id) {
	$('assortiment_tekst').style.display='none';
}

function $(id){
	return document.getElementById(id);	
}

var curback=0;
function randomBack(){
	$('docbody').style.backgroundImage='url('+achtergronden[curback]+')';
	curback++;
	if (curback>=achtergronden.length) {curback=0;}
}