change JavaScript Google Map marker color

color_marker_function.js

let map;
// global array to store the marker object 
let markersArray = [];

function initMap() {
  map = new google.maps.Map(document.getElementById('map'), {
    center: {lat: -34.397, lng: 150.644},
    zoom: 8
  });
  addMarker({lat: -34.297, lng: 150.544}, "yellow");
  addMarker({lat: -34.397, lng: 150.644}, "green");
  addMarker({lat: -34.597, lng: 150.844}, "blue");
}

function addMarker(latLng, color) {
  let url = "http://maps.google.com/mapfiles/ms/icons/";
  url += color + "-dot.png";

  let marker = new google.maps.Marker({
    map: map,
    position: latLng,
    icon: {
      url: url
    }
  });

  //store the marker object drawn in global array
  markersArray.push(marker);
}