function helpVoorwaarden() {
    popup("http://documentatie.zwijsen.nl/algemeen/AVW_ICT_Zwijsen.pdf", "zwijsen_algemene_voorwaarden");
}
function helpContact() {
    window.location.href = "mailto:klantenservice@zwijsen.nl";
}
function popup(url, id) {
 	var w  = screen.availWidth-100;
 	var h =  screen.availHeight-100;
 	var left   = 50;
 	var top    = 50;
 	var params = 'width='+w+', height='+h;
 	params += ', top='+top+', left='+left;
 	params += ', directories=no';
 	params += ', location=no';
 	params += ', menubar=no';
 	params += ', resizable=yes';
 	params += ', scrollbars=no';
 	params += ', status=no';
 	params += ', toolbar=no';
 	newwin = window.open(url, id, params);
 	if(newwin) {
 		newwin.focus();
		//if (window.focus) newwin.focus();
 		return true;
 	} else {
 		return false;
 	}
}