function zamknij(cel){
	var co = document.getElementById(cel);
	if(co.style.display == 'block' || co.style.visibility == 'visible'){
		co.style.display = 'none';
		co.style.visibility = 'hidden';
	} else {
		co.style.display = 'block';
		co.style.visibility = 'visible';
	}
}