Google Maps loads to the right of the marker!

For some reason, Google Maps is loading the following map with the marker to the left - I have no idea why.

I've got this page in an iFrame, which is getting loaded in a lightbox, but an issue is it doesn't load the map exactly ON the marker, it's always down to the left.

   <link href="https://code.google.com/apis/maps/documentation/javascript/examples/standard.css" rel="stylesheet" type="text/css" /> 
<script type="text/javascript" src="https://maps.google.com/maps/api/js?sensor=false"></script> 
<script type="text/javascript"&开发者_如何学编程gt; 
  var geocoder;
  var map;
  function initialize() {
    geocoder = new google.maps.Geocoder();
    var latlng = new google.maps.LatLng(-0, 0);
    var myOptions = {
      zoom: 15,
      center: latlng,
      mapTypeId: google.maps.MapTypeId.ROADMAP
    }
    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
  }

  function codeAddress() {
    var address = '1 Dover Street, London, United Kingdom';

    geocoder.geocode( { 'address': address}, function(results, status) {
      if (status == google.maps.GeocoderStatus.OK) {

        var latlng = new google.maps.LatLng(results[0].geometry.location);
        var myOptions = {
            zoom: 15,
            center: latlng,
            mapTypeId: google.maps.MapTypeId.ROADMAP
        }

        map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);  
        map.setCenter(results[0].geometry.location);
        var marker = new google.maps.Marker({
            map: map, 
            position: results[0].geometry.location
        });
      } else {
        //alert("Geocode was not successful for the following reason: " + status);
      }
    });
  }
</script> 

If anyone could let me know why it's doing that, that would be great!

Thanks!