datetoday = new Date();
timenow=datetoday.getTime();
datetoday.setTime(timenow);
thehour = datetoday.getHours();
if (thehour >19) display = "Abend";
else if (thehour >10) display = "Tag";
else display = "Morgen";
var greeting = ("Guten " + display + "!");
document.write(greeting);