reset_color_of_markers_of_mapbox.js

function reset_colors(map) {
  var layer = map.featureLayer,
      geoJson = layer.getGeoJSON(),
      features = geoJson.features;
  for (var i = 0; i < features.length; i++) {
      features[i].properties['marker-color'] = "#0F86BD";
  }
  layer.setGeoJSON(geoJson);
}