Do you know VBScript for HTML?!
<html>
<body>
<script type="text/vbscript">
Function greeting()
i=hour(time)
If i < 10 Then
document.write("Good morning!")
Else
document.write("Have a nice day!")
End If
End Function
</script>
</head>
<body onload="greeting()">
</body>
</html>
If not, try
Google[
^].