JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://openlayers.org/en/master/build/ol.js"></script>
<link rel="stylesheet" href="http://openlayers.org/en/v3.0.0/css/ol.css">
<title>Export map example</title>
<body>
    <div id="container">
        <div id="map"></div>
    </div>
</body>

CSS

#map { width: 100%; height: 100%;}

JavaScript

var styles = [
      new ol.style.Style({
          image: new ol.style.Circle({
            radius: 5,
              fill: new ol.style.Fill({
                  color: 'rgb(0, 0, 255)'
              }),
            stroke: new ol.style.Stroke({color: 'blue', width: 2})
          }),
          geometry: function(feature) {
              var coordinates = feature.getGeometry().getCoordinates()[0];
              return new ol.geom.MultiPoint(coordinates);
          }
      }),
      new ol.style.Style({
        stroke: new ol.style.Stroke({
          color: 'blue',
          width: 3
        }),
        fill: new ol.style.Fill({
          color: 'rgba(0, 0, 255, 0.1)'
        })
      })
];

var source = new ol.source.GeoJSON(
    /** @type {olx.source.GeoJSONOptions} */ ({
      object: {
        'type': 'FeatureCollection',
        'crs': {
          'type': 'name',
          'properties': {
            'name': 'EPSG:3857'
          }
        },
        'features': [
          {
            'type': 'Feature',
            'geometry': {
              'type': 'Polygon',
                'coordinates': [[[-5e6, 6e6], [-5e6, 8e6], [-3e6, 8e6],
                    [-3e6, 6e6], [-5e6, 6e6]]]
            }
          },
          {
            'type': 'Feature',
            'geometry': {
              'type': 'Polygon',
              'coordinates': [[[-2e6, 6e6], [-2e6, 8e6], [0, 8e6],
                    [0, 6e6], [-2e6, 6e6]]]
            }
          },
          {
            'type': 'Feature',
            'geometry': {
              'type': 'Polygon',
              'coordinates': [[[1e6, 6e6], [1e6, 8e6], [3e6, 8e6],
                    [3e6, 6e6], [1e6, 6e6]]]
            }
          },
          {
            'type': 'Feature',
            'geometry': {
              'type': 'Polygon',
              'coordinates': [[[-2e6, -1e6], [-1e6, 1e6],
                  [0, -1e6], [-2e6, -1e6]]]
            }
          }
        ]
      }
    }));

var layer = new...