var t, lit, i;

function onclickspan(liter, span) {
	span.className = (span.className == 'b-left-menu-item-close') ? 'b-left-menu-item-open' : 'b-left-menu-item-close';
	tree(liter);
}

function tree(liter) {
	lit = liter;
	i = 1;
	t = setInterval(show, 75);
}

function show() {
	var el;
	if (el = document.getElementById(lit + i)) {
		el.style.display = (el.style.display == 'block') ? 'none' : 'block';
		i++;
	}
	else clearInterval(t);
}