var now = new Date();
var hour = now.getHours();

if(hour >= 1 && hour <= 11){
	src = "images/morning.png";
}else if(hour >= 11 && hour <= 17){
	src = "images/afternoon.png";
}else{
	src = "images/evening.png";
}

document.write('<img src="'+src+'" width="303" height="142">');