var panels = new Array('panel1', 'panel2', 'panel3', 'panel4', 'panel5', 'panel6');

function showPanel(a, name) {
	for(i = 0; i < panels.length; i++) {
		try {
			document.getElementById(panels[i]).style.display = (name == panels[i]) ? 'block':'none';
		} catch(er) {
			// do nothing
		}
	}
	return false;
}
function loader() {
	showPanel(false, 'panel1');
}

var ss = document.styleSheets[0];
if (ss.insertRule) {
	ss.insertRule(".hide { display: none }", 0); // Mozilla
} else if (ss.addRule) {
	ss.addRule(".hide", "display: none"); // IE
}


function isDefined(property) {
  return (typeof property != 'undefined');
}

if (isDefined(window.addEventListener)) {
	window.addEventListener('load', loader, false);
} else if (isDefined(window.attachEvent)) {
	window.attachEvent('onload', loader);
} else {
	window.onload = showPanel(false, 'panel1');
}