JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://maps.googleapis.com/maps/api/js?v=3.exp"></script>
<div id="map">

</div>

CSS

#map {
  height: 400px;
  width: 400px;
}
#legend1 {
    width: 90px;
    background: #FFF;
    padding: 10px;
    margin: 5px;
    font-size: 8px;
    font-family: Arial, sans-serif;
    border: 1px solid black;
}

JavaScript

google.maps.event.addDomListener(window, 'load', initialize);

function initialize() {

 var map = new google.maps.Map(document.getElementById('map'), {
    zoom: 5,
    center: {lat: 24.886, lng: -70.268},
    mapTypeId: google.maps.MapTypeId.TERRAIN
  });

  // Define the LatLng coordinates for the polygon's path.
  var triangleCoords = [
    {lat: 25.774, lng: -80.190},
    {lat: 18.466, lng: -66.118},
    {lat: 32.321, lng: -64.757},
    {lat: 25.774, lng: -80.190}
  ];

  // Construct the polygon.
  var bermudaTriangle = new google.maps.Polygon({
    paths: triangleCoords,
    strokeColor: '#FF0000',
    strokeOpacity: 0.8,
    strokeWeight: 2,
    fillColor: '#FF0000',
    fillOpacity: 0.35
  });
  bermudaTriangle.setMap(map);
}