Как изменить формат времени JS?

<script>
var h = (new Date()).getHours();                  
if( h > 8 && h <  23 ) {
    $('.gid_mesto').addClass('Go');
}
</script>

<script>
var h = (new Date()).getHours(); 
if( h > "8:00" && h < "23:00" ) {
    $('.gid_mesto').addClass('Go');
}
</script>

var now = new Date;
var hours = now.getHours();
var seconds = now.getSeconds();
var time = hours + ':' + (seconds < 10 ? '0' + seconds : seconds);
if (time > '8:00' && time < '23:00') {
	$('.gid_mesto').addClass('Go');
}