function zobrazASkry(idecko){
	el=document.getElementById(idecko).style; 
	if (el.display == 'block') {
		el.display = 'none';
		if (idecko == 'audio') document.images['minus'].src='./subory/obrazky/plus.png';
		else document.images['minus1'].src='./subory/obrazky/plus.png';	
	}
	else {
		el.display = 'block';
		if (idecko == 'audio') document.images['minus'].src='./subory/obrazky/minus.png';
		else document.images['minus1'].src='./subory/obrazky/minus.png'
	}
}

var zobrazena = "necakam";
function zobraz(polozka){
	if (document.getElementById){
		document.getElementById(zobrazena).style.display = "none";
		document.getElementById(polozka).style.display = "block";
		zobrazena = polozka;
		return false;
	}
	else {
		if(document.stylesheets) document.stylesheets["zalozky"].disabled = true;
		return true;
	} 
}