JSFiddle - React, Tailwind, and code Playground

HTML

<div id="map"></div>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>

CSS

#map {
        height: 100%;
      }
html, body {
        height: 100%;
        margin: 0;
        padding: 0;
      }

JavaScript

var citymap = {
        antwerpen: {
          //center: {lat: 51.22131939707599, lng: 4.399144649505615},
          center: {lat: 51.219448, lng: 4.402464},
          radius: 28000,
          color: '#FF0000'
        },
        sintniklaas: {
          //center: {lat: 51.16471889365012, lng: 4.139378070831299},
          center: {lat: 51.155884, lng: 4.154441},
          radius: 41000,
          color: '#00FF00'
        },
        hasselt: {
          //center: {lat: 50.93105583426365, lng: 5.336930751800537},
          center: {lat: 50.930690, lng: 5.332480},
          radius: 85000,
          color: '#0000FF'
        },
        brugge: {
          //center: {lat: 51.208335264580036, lng: 3.227062225341797},
          center: {lat: 51.209348, lng: 3.224700},
          radius: 91000,
          color: '#00AAAA'
        },
        essen: {
          center: {lat: 51.4643684068504, lng: 4.473130702972412},
          //center: {lat: 51.467760, lng: 4.468440},
          radius: 500,
          color: '#000000'
        },
      };

      $( document ).ready(function() {
        // Create the map.
        var myLatLng = {lat: 51.4677662, lng: 4.4684089};

        var map = new google.maps.Map(document.getElementById('map'), {
          zoom: 11,
          center: myLatLng,
          mapTypeId: 'terrain'
        });
        
        var infowindow = new google.maps.InfoWindow({
          content: "Café In den Toren",
          //pixelOffset: new google.maps.Size(0,100)
        });

        var marker = new google.maps.Marker({
          position: myLatLng,
          map: map,
        });

        //infowindow.open(map,marker);

        // Construct the circle for each value in citymap.
        // Note: We scale the area of the circle based on the population.
        for (var city in citymap) {
          // Add the circle for this city to the map.
          var cityCircle = new google.maps.Circle({
            strokeColor: citymap[city].color,
            strokeOpacity:...