Google Map is gray color
<p>my google maps script is gray when load the page, when I open the inspector of elements seen, I think it's for the resize, you can be? Thanks friends, I expect an answer. Here you have all the html of what would be the map, then this is included within a div. The strange thing is that when you resize the screen, is observed. I need help!!!!</p>

<pre><code>&lt;!DOCTYPE html&gt;
&lt;html&gt;
&lt;head&gt;
&lt;style type="text/css"&gt;

#googleMap {
 width: 100%;
height: 600px;
margin-top: 6.5%;
  overflow:visible;

 }
      img, embed, object, video {
  max-width: 100%;
  max-height: 100%;
  width: auto;
  height: auto;
 }



 &lt;/style&gt;
 &lt;script src="https://maps.googleapis.com/maps/api/js?      key=AIzaSyCbVI4cT8PjwlmV0pZfK961MGnd6H3aGoY&amp;signed_in=false"&gt; &lt;/script&gt;

&lt;script&gt;

 var myCenter=new google.maps.LatLng(39.287649, -0.422548);
var myCenterverd=new google.maps.LatLng(39.287413, -0.422255);
var myCenterroig=new google.maps.LatLng(39.288497, -0.423953);
var myCentergroc=new google.maps.LatLng(39.287766, -0.421604);


 function initialize() {
  var mapOptions = {
   center:new google.maps.LatLng(39.287413, -0.422255),
   zoom:8,
    mapTypeId:google.maps.MapTypeId.ROADMAP,
   //disableDefaultUI: true
    };
    var map=new google.maps.Map(document.getElementById("googleMap"), mapOptions);

  //var marker=new google.maps.Marker({position:myCenter,icon:'gotaico.png'});
   var markerverd=new google.maps.Marker({position:myCenterverd,icon:'../dashboard/include/Mapa/iconosrellenos/gotaicoverd.png'});
   var markerroig=new google.maps.Marker({position:myCenterroig,icon:'../dashboard/include/Mapa/iconosrellenos/gotaicoroig.png'});
   var markergroc=new google.maps.Marker({position:myCentergroc,icon:'../dashboard/include/Mapa/iconosrellenos/gotaicogroc.png'});

   //marker.setMap(map);
  markerverd.setMap(map);
  markerroig.setMap(map);
  markergroc.setMap(map);
 }

 google.maps.event.addDomListener(window, 'load', initialize);
&lt;/script&gt;
&lt;/head&gt;

 &lt;body&gt;
 &lt;div id="googleMap"&gt;&lt;/div&gt;

 &lt;/body&gt;
 &lt;/html&gt;
</code></pre>