var tempo = 300;
var imgfx;
function initMainAnchor(a) {
	if (a.getParent().getProperty('class').indexOf('active') != -1) return;
	a.onmouseover = function() {
		imgfx.cancel();
		imgfx.start('opacity', 0);
	}
	a.onmouseout = function() {
		imgfx.cancel();
		imgfx.start('opacity', 1);
	}
}
window.addEvent(
	'domready', 
	function() {
		var img = $$('div#topimage')[0];
		imgfx = new Fx.Tween(img, {
		    duration: tempo
		});
		imgfx.set('opacity', 1);
		var maina = $$('ul#mainmenu')[0].getElements('a');
		for (var i = 0; i < maina.length; i++) {
			initMainAnchor(maina[i]);
		}
	}
);