Code
<script language="JavaScript">
<!--
var h=(new Date()).getHours();
if (h > 24 || h < 6) document.write('Ar labunakti') ;
if (h > 6 && h < 12) document.write('Labrīt');
if (h > 12 && h < 19) document.write('Labdien');
if (h > 19 && h < 24) document. write('Labvakar');
//-->
</script>
