function menu_block (param) {
	var podmenu = document.getElementById(param);
	podmenu.style.display = 'block';	
}

function menu_none (param) {
	var podmenu = document.getElementById(param);
	podmenu.style.display = 'none';
}

function menu_catalog (plus,visible){
	
	var podkatalog = document.getElementById(visible); 
	var plus_ok = document.getElementById(plus);
	if(podkatalog.style.display == 'none')
		{
			podkatalog.style.display = 'block';	
			plus_ok.innerHTML = '–';		//alert ("sd");
		}
	else
		{
			podkatalog.style.display = 'none';
			plus_ok.innerHTML = '+';		
		}
}