CODE EXAMPLE FOR CSS

Grayscale Style

[
    {
        "featureType": "all",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "administrative",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "administrative",
        "elementType": "labels.text.fill",
        "stylers": [
            {
                "color": "#444444"
            },
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "administrative.neighborhood",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "landscape",
        "elementType": "all",
        "stylers": [
            {
                "visibility": "on"
            },
            {
                "color": "#e0dfe0"
            }
        ]
    },
    {
        "featureType": "landscape",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "poi",
        "elementType": "all",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "poi",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "poi.park",
        "elementType": "geometry",
        "stylers": [
            {
                "color": "#a8a9a8"
            },
            {
                "visibility": "on"
            }
        ]
    },
    {
        "featureType": "road",
        "elementType": "all",
        "stylers": [
            {
                "saturation": -100
            },
            {
                "lightness": 45
            }
        ]
    },
    {
        "featureType": "road",
        "elementType": "geometry.fill",
        "stylers": [
            {
                "visibility": "on"
            },
            {
                "color": "#5b5b5a"
            }
        ]
    },
    {
        "featureType": "road",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "road.highway",
        "elementType": "all",
        "stylers": [
            {
                "visibility": "simplified"
            }
        ]
    },
    {
        "featureType": "road.highway",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "road.arterial",
        "elementType": "labels.icon",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "transit",
        "elementType": "all",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "transit",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    },
    {
        "featureType": "water",
        "elementType": "all",
        "stylers": [
            {
                "color": "#ffffff"
            },
            {
                "visibility": "on"
            }
        ]
    },
    {
        "featureType": "water",
        "elementType": "labels",
        "stylers": [
            {
                "visibility": "off"
            }
        ]
    }
]