add google Map

gistfile1.txt

<div id="map"></div>
<script  src="https://maps.googleapis.com/maps/api/js?key=KEY_NUMBER" ></script>

function initMap() {
  var myLatLng = {lat: 41.892896, lng: -87.638387};

  var map = new google.maps.Map(document.getElementById('map'), {
    center: {lat: 41.892896, lng: -87.638387},
    zoom: 15,
    styles: [
            {
                "featureType": "water",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#e9e9e9"
                    },
                    {
                        "lightness": 17
                    }
                ]
            },
            {
                "featureType": "landscape",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#f5f5f5"
                    },
                    {
                        "lightness": 20
                    }
                ]
            },
            {
                "featureType": "road.highway",
                "elementType": "geometry.fill",
                "stylers": [
                    {
                        "color": "#ffffff"
                    },
                    {
                        "lightness": 17
                    }
                ]
            },
            {
                "featureType": "road.highway",
                "elementType": "geometry.stroke",
                "stylers": [
                    {
                        "color": "#ffffff"
                    },
                    {
                        "lightness": 29
                    },
                    {
                        "weight": 0.2
                    }
                ]
            },
            {
                "featureType": "road.arterial",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#ffffff"
                    },
                    {
                        "lightness": 18
                    }
                ]
            },
            {
                "featureType": "road.local",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#ffffff"
                    },
                    {
                        "lightness": 16
                    }
                ]
            },
            {
                "featureType": "poi",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#f5f5f5"
                    },
                    {
                        "lightness": 21
                    }
                ]
            },
            {
                "featureType": "poi.park",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#dedede"
                    },
                    {
                        "lightness": 21
                    }
                ]
            },
            {
                "elementType": "labels.text.stroke",
                "stylers": [
                    {
                        "visibility": "on"
                    },
                    {
                        "color": "#ffffff"
                    },
                    {
                        "lightness": 16
                    }
                ]
            },
            {
                "elementType": "labels.text.fill",
                "stylers": [
                    {
                        "saturation": 36
                    },
                    {
                        "color": "#333333"
                    },
                    {
                        "lightness": 40
                    }
                ]
            },
            {
                "elementType": "labels.icon",
                "stylers": [
                    {
                        "visibility": "off"
                    }
                ]
            },
            {
                "featureType": "transit",
                "elementType": "geometry",
                "stylers": [
                    {
                        "color": "#f2f2f2"
                    },
                    {
                        "lightness": 19
                    }
                ]
            },
            {
                "featureType": "administrative",
                "elementType": "geometry.fill",
                "stylers": [
                    {
                        "color": "#fefefe"
                    },
                    {
                        "lightness": 20
                    }
                ]
            },
            {
                "featureType": "administrative",
                "elementType": "geometry.stroke",
                "stylers": [
                    {
                        "color": "#fefefe"
                    },
                    {
                        "lightness": 17
                    },
                    {
                        "weight": 1.2
                    }
                ]
            }
        ]
  });

  var marker = new google.maps.Marker({
    position: myLatLng,
    map: map,
    title: 'Hello World!'
  });
};