function viditelnost(cat,tit) {
		obsah=document.getElementById("cat"+cat+"_content");
		if (tit==1) titulek=document.getElementById("cat"+cat);
        if (obsah.style.display=="none") {
			obsah.style.display="block";
			if (tit==1) titulek.className="open";
			window.frames.sync.location="/sync.php?action=shop_category&status=open&id="+cat;  
		} else {
			if (tit==1) obsah.style.display="none";
			if (tit==1) titulek.className="close";
			if (tit==1) window.frames.sync.location="/sync.php?action=shop_category&status=close&id="+cat;   
		};	
};