function klikgastenboek() {
	var thediv='gbdiv'; 
	var mydiv=document.getElementById(thediv);
	if (mydiv.style.visibility=='visible') {
		mydiv.style.visibility='hidden';
		mydiv.style.display='none';
	}
	else {	
		mydiv.style.visibility='visible';
		mydiv.style.display='block';
	}
}	

function kliksldiv(id) {
	var thediv="sldiv_"+id;
	var mydiv=document.getElementById(thediv);
	if (mydiv.style.visibility=="visible") {
		mydiv.style.visibility="hidden";
		mydiv.style.display="none";
	}
	else {
		mydiv.style.visibility="visible";
		mydiv.style.display="block";
	}
}