var cats = new Array();

cats[0] = new Array("houses", '-521px -1px');
cats[1] = new Array("other", '-261px -1px');
cats[2] = new Array("flat", '-131px -1px');
cats[3] = new Array("contact", '-391px -1px');
cats[4] = new Array("newhouses", '-651px -1px');

function homeRolls() {
	if (!document.getElementById) return false;
	if (!document.getElementsByTagName) return false;
	
	var links = document.getElementsByTagName("a");
	for (var i=0; i < links.length; i++) {
    	if (links[i].className.match("intro_rolls")) {
			links[i].onmouseover = function() {
				var cat = this.id.substring(5,this.id.length);
				for(i=0; i<cats.length; i++) {
					if (cats[i][0] == cat) {
						val = cats[i][1];
						break;
					}
				}

				document.getElementById('roll_images').style.backgroundPosition=val;
				document.getElementById('description_box_default').style.display='none';
				document.getElementById('description_box_'+cat).style.display='block';
			}
			
			links[i].onmouseout = function() {
				var cat = this.id.substring(5,this.id.length);
				
				document.getElementById('roll_images').style.backgroundPosition='-1px -1px';
				document.getElementById('description_box_'+cat).style.display='none';
				document.getElementById('description_box_default').style.display='block';
			}
		}
	}
}

Event.observe(window, 'load', homeRolls, false);