单击地图标记时平滑滚动

我有一个地图，我显示多个标记，如果一个标记被点击，你去到页面底部的div(经典锚链接)

有人能告诉我为什么我没有平滑滚动时，我点击标记，但我确实有，如果我只是创建一个链接和一个div的ID?

这是js:

  jQuery(function($) {
    // Asynchronously Load the map API 
    var script = document.createElement('script');
    script.src = "http://maps.googleapis.com/maps/api/js?sensor=false&callback=initialize";
    document.body.appendChild(script);
});
function initialize() {
    var map;
    var bounds = new google.maps.LatLngBounds();
    var mapOptions = {
        mapTypeId: 'roadmap'
    };
    // Display a map on the page
    map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
    map.setTilt(45);
    // Multiple Markers
    var markers = [
        ['London Eye, London', 51.503454,-0.119562, '#1'],
        ['Palace of Westminster, London', 51.499633,-0.124755, '#2']
    ];

    // Display multiple markers on a map
    var infoWindow = new google.maps.InfoWindow(), marker, i;
    // Loop through our array of markers & place each one on the map  
    for( i = 0; i < markers.length; i++ ) {
        var position = new google.maps.LatLng(markers[i][1], markers[i][2]);
        bounds.extend(position);
        marker = new google.maps.Marker({
            position: position,
            map: map,
            title: markers[i][0],
            url: markers[i][3]
        });

       google.maps.event.addListener(marker, 'click', function() { 
       window.location.hash = this.url;
    }); 
            $(document).ready(function(){
                $('a[href^="#"]').on('click',function (e) {
                    e.preventDefault();
                    var target = this.hash,
                    $target = $(target);
                    $('html, body').stop().animate({
                        'scrollTop': $target.offset().top
                    }, 900, 'swing', function () {
                        window.location.hash = target;
                    });
                });
            });

        // Automatically center the map fitting all markers on the screen
        map.fitBounds(bounds);
    }
    // Override our map zoom level once our fitBounds function runs (Make sure it only runs once)
    var boundsListener = google.maps.event.addListener((map), 'bounds_changed', function(event) {
        this.setZoom(14);
        google.maps.event.removeListener(boundsListener);
    });
}