Neatline - adding a new basemap / map style

Hi
I have a newbie question:

I want to change the color of my basemap.

I have a Google Maps API v3 Styled Maps JSON like this:
[ { "featureType": "water", "stylers": [ { "hue": "#0099ff" }, { "lightness": 58 }, { "saturation": -29 } ] }]

But I can't figure out were to add this.