JSON style does not working?

Hi, I am trying to use Custom Map Styles option with no success.
(By the way – the url over the help instruction to the Styled Map Wizzard go to 404.)
I used current map style wizzard.
However it does not work.
My style is:

[
  {
    "featureType": "administrative",
    "elementType": "labels.text.fill",
    "stylers": [
      {
        "color": "#222222"
      },
      {
        "weight": "1"
      }
    ]
  },
  {
    "featureType": "landscape",
    "stylers": [
      {
        "color": "#ffffff"
      }
    ]
  },
  {
    "featureType": "landscape",
    "elementType": "geometry.stroke",
    "stylers": [
      {
        "color": "#dddddd"
      }
    ]
  },
  {
    "featureType": "poi",
    "stylers": [
      {
        "visibility": "off"
      }
    ]
  },
  {
    "featureType": "poi.attraction",
    "stylers": [
      {
        "hue": "#ff0000"
      },
      {
        "saturation": "-100"
      },
      {
        "lightness": "0"
      },
      {
        "gamma": "3.00"
      },
      {
        "visibility": "simplified"
      }
    ]
  },
  {
    "featureType": "poi.business",
    "stylers": [
      {
        "hue": "#ff0000"
      },
      {
        "saturation": "-100"
      },
      {
        "lightness": "0"
      },
      {
        "gamma": "3.00"
      },
      {
        "visibility": "simplified"
      }
    ]
  },
  {
    "featureType": "road",
    "stylers": [
      {
        "color": "#999999"
      }
    ]
  },
  {
    "featureType": "road",
    "elementType": "labels.text.stroke",
    "stylers": [
      {
        "color": "#ffffff"
      }
    ]
  },
  {
    "featureType": "transit",
    "stylers": [
      {
        "visibility": "off"
      }
    ]
  },
  {
    "featureType": "water",
    "stylers": [
      {
        "color": "#b3c8fb"
      },
      {
        "lightness": "50"
      },
      {
        "gamma": "1"
      },
      {
        "visibility": "on"
      }
    ]
  }
]

API key is ok. No errors in console etc…
Should I do something else to make it work?

Thanks in advance for help.

Best for you.
Dominik