<script>
var tanggal = '';
var jam = '';
$(this).change(function () {
    var limit = new Date().getTime() + (8 * 6 * 6 * 1000);
    limit = new Date(limit);
    tanggal = $('#tanggal')[0].value;
    var input = new Date(tanggal + " 00:00:00");
    if ($('#jam')[0].value != '') {
        var jam = $('#jam')[0].value;
        input = input.getTime() + (jam * 60 * 60 * 1000);
        input = new Date(input);
        if (limit < input) {
            alert("limit: " + limit + "\n" + input + "\nBoleh");
        } else {
            alert("limit: " + limit + "\n" + input + "\nTydack Bisa");
        }
    }
});
</script>