移动设备上的谷歌地图缩放级别

是否只能在手机上更改缩放?

HTML格式

<div class="row">
  <div class="col-xs-12 col-sm-12 col-md-12">
    <div id="map"></div>
  </div>
</div>

CSS格式

#map {
  height: 400px;
  width: 100%;
  background-color: grey;
}

<script>
  function initMap() {
    var center = {lat: 56.463415, lng: 9.495170};
    var locations = [

      ['Headline', 'Headline<br>Address<br><a href="#" target="_blank">Show direction</a>', 1.686340, 15.998270],

    ];

    var map = new google.maps.Map(document.getElementById('map'), {
    zoom: 7,
    center: center
    });
    var infowindow = new google.maps.InfoWindow({});
    var marker, count;
    for (count = 0; count < locations.length; count++) {
      marker = new google.maps.Marker({
        position: new google.maps.LatLng(locations[count][2], locations[count][3]),
        map: map,
        title: locations[count][0]
      });
      google.maps.event.addListener(marker, 'click', (function(marker, count) {
        return function() {
          infowindow.setContent(locations[count][1]);
          infowindow.open(map, marker);
        }
      })(marker, count));
    }
  }
  google.maps.event.addDomListener(window, 'load', initMap);
</script>