var active = 1;

function showItem(id) {

	document.getElementById('item-' + active).style.display = 'none';
	document.getElementById('list-' + active).className = '';

	active = id;

	document.getElementById('item-' + active).style.display = 'block';
	document.getElementById('list-' + active).className = 'active';
	document.getElementById('banner').style.backgroundImage = "url('_images/banner" + active + ".jpg')";

}