function toggle_hide(objectId) {
	
	var obj = document.getElementById(objectId);
	
	if ( obj.style.display != 'block') {
		obj.style.display = 'block';
	}
	else {
		obj.style.display = 'none';
	}
	
	return false;
}

// note that element to be centered has to be called
// "main" in order for following handle to work
window.onresize = handleResize;

// this stores currently active menu button
var activeId = "";