main.js

var L = require('leaflet');
require('esri-leaflet');
var popupTemplate = require('.src/popup.js');

var node = L.DomUtil.create('div', 'map-div', document.body);

var map = L.map(node).setView([45.528, -122.680], 13);

L.esri.basemapLayer('Gray').addTo(map);

var parks = new L.esri.FeatureLayer('http://services.arcgis.com/rOo16HdIMeOBI4Mb/arcgis/rest/services/Portland_Parks/FeatureServer/0', {
  style: function () {
    return { color: '#70ca49', weight: 2 };
  }
}).addTo(map);

parks.bindPopup(popupTemplate);