Zoom Based Styling

style.css

@width: 2;

#layer {
  marker-width: @width;
  marker-fill: ramp([arrest_char], (#ffdd00, #1dae00), ("Not arrested", "Arrested"), "=");
  marker-fill-opacity: 1;
  marker-allow-overlap: true;
  marker-line-width: 0;
  marker-line-color: #FFF;
  marker-line-opacity: 1;
  marker-comp-op: multiply;
  
  [zoom>12]{marker-width: @width*2;}
  [zoom>14]{marker-width: @width*4;}
  [zoom>16]{marker-width: @width*6;}
  [zoom>18]{marker-width: @width*8;}
 
}