function submenu(idx) {
	if (idx == active) return;

	document.getElementById('submenu'+active).style.display = 'none';
	document.getElementById('menu'+active).className = 'menu';
	document.getElementById('menu'+idx).className = 'menu active';

	var callback = function () {
		$('#submenu'+idx).fadeIn(250);
	}

	if (idx > active) {
		for (var i = active+1; i <= idx; ++i) {
			$('#menu'+i).animate({ left: 1+50*i },
			                     250,
			                     'easeOutExpo',
			                     i == idx ? callback : null);
		}
	} else {
		for (var i = active; i > idx; --i) {
			$('#menu'+i).animate({ left: 916-50*(count-i) },
			                     250,
			                     'easeOutExpo',
			                     i == idx+1 ? callback : null);
		}
	}

	active = idx;
}