var logosOnLoad = function () {
		var entranceLogos = getElementsByTagAndClassName("img", "entranceLogo");
		for(var i = 0; i< entranceLogos.length; i++)
		{
 		 connect(entranceLogos[i], "onmouseenter", appearLogo); 
 		 connect(entranceLogos[i], "onmouseleave", disappearLogo); 
		 }
};

connect(window, "onload", logosOnLoad);

var appearLogo = function(e){
  var target = e.target();
	Opacity(target, {to:1, from:0.5}); 
};

var disappearLogo = function(e){
 var target = e.target();
 Opacity(target, {from:1, to:0.5});
};