GeoChart Google Style Markers

google.charts.load('42', {
  'packages': ['geochart']
});
google.charts.setOnLoadCallback(drawVisualization);

function drawVisualization() {

  var data = new google.visualization.DataTable();

  data.addColumn('number', 'Lat');
  data.addColumn('number', 'Lon');
  data.addColumn('string', 'Country');
  data.addColumn('number', 'value');
  data.addColumn({
    type: 'string',
    role: 'tooltip'
  });

  var img_urls = {
    'Colombia': "https://i.ibb.co/4PMF2Jh/MAPAS-CO.png",
    'Argentina': "https://i.ibb.co/dtYqm6Q/MAPAS-AR.png",
    'Lesotho': "https://i.ibb.co/yF2w9FS/MAPAS-LS.png",
    'Eswatini': "https://i.ibb.co/0m0hKrm/MAPAS-ESWATINI-06.png",
    'Uganda': "https://i.ibb.co/k67BkDz/MAPAS-UG.png",
    'Botswana': "https://i.ibb.co/qmg2cw3/MAPAS-BW.png",
    'Angola': "https://i.ibb.co/LPtm8VJ/MAPAS-AO.png",
    'Romania': "https://i.ibb.co/hH29SnL/MAPAS-RO.png",
    'Tanzania': "https://i.ibb.co/jyKLbLn/MAPAS-TZ.png",
    'Malawi': "https://i.ibb.co/pn32frh/MAPAS-MW.png"
  }

  //  var ivalue = new Array();

  data.addRows([
    [4.711, -74.0721, 'Colombia', 0, '']
  ]);
  //  data.addRows([[4.711,-74.0721,'Colombia']]);
  //  data.addRows([[4.711,-74.0721,'Colombia']]);
  //  ivalue['4.711'] = '';

  data.addRows([
    [-34.6037, -58.3816, 'Argentina', 1, '']
  ]);
  // data.addRows([[-34.6037,-58.3816,'Argentina']]);
  //  ivalue['-34.6037'] = '';

  data.addRows([
    [-29.61, 28.2336, 'Lesotho', 2, '']
  ]);
  // data.addRows([[-29.61,28.2336,'Lesotho']]);
  //  ivalue['-29.61'] = '';

  data.addRows([
    [-22.3285, 24.6849, 'Botswana', 3, '']
  ]);
  // data.addRows([[-22.3285,24.6849,'Botswana']]);
  //  ivalue['-22.3285'] = '';

  data.addRows([
    [-26.5225, 31.4659, 'Eswatini', 4, '']
  ]);
  //  data.addRows([[-26.5225,31.4659,'Eswatini']]);
  //  ivalue['-26.5225'] = '';

  data.addRows([
    [1.3733, 32.2903, 'Uganda', 5, '']
  ]);
  // data.addRows([[1.3733,32.2903,'Uganda']]);
  //  ivalue['1.3733'] = '';

  data.addRows([
    [-11.2027, 17.8739, 'Angola', 6, '']
  ]);
  //  data.addRows([[-11.2027,17.8739,'Angola']]);
  //  ivalue['-11.2027'] = '';

  data.addRows([
    [-13.2543, 34.3015, 'Malawi', 7, '']
  ]);
  //  data.addRows([[-13.2543,34.3015,'Malawi']]);
  //  ivalue['-13.2543'] = '';

  data.addRows([
    [-6.369, 34.8888, 'Tanzania', 8, '']
  ]);
  //  data.addRows([[-6.369,34.8888,'Tanzania']]);
  //  ivalue['-6.369'] = '';

  data.addRows([
    [45.9432, 24.9668, 'Romania', 9, '']
  ]);
  //  data.addRows([[45.9432,24.9668,'Romania']]);
  //  ivalue['45.9432'] = '';

  var options = {
    backgroundColor: {
      fill: '#FFFFFF',
      stroke: '#FFFFFF',
      strokeWidth: 0
    },
    colorAxis: {
      minValue: 0,
      maxValue: 9,
      colors: ['#6699CC', '#6699CC', '#6699CC', '#6699CC', '#6699CC', '#6699CC', '#6699CC', '#6699CC', '#6699CC', '#6699CC']
    },
    legend: 'none',
    datalessRegionColor: '#f5f5f5',
    displayMode: 'markers',
    enableRegionInteractivity: 'true',
    resolution: 'countries',
    sizeAxis: {
      minValue: 1,
      maxValue: 1,
      minSize: 5,
      maxSize: 5
    },
    region: 'world',
    keepAspectRatio: true,
    width: 600,
    height: 400,
    tooltip: {
      textStyle: {
        color: '#444444'
      },
      trigger: 'focus',
      isHtml: true
    }
  };


  var chart = new google.visualization.GeoChart(document.getElementById('map'));

  var modal = document.getElementById("myModal");
  var modalImg = document.getElementById("img01");
  var span = document.getElementById("close");

  google.visualization.events.addListener(chart, 'select', function() {
    var selection = chart.getSelection();
    var value = data.getValue(selection[0].row, 2);
    console.log(value);

    modal.style.display = "block";
    modalImg.src = img_urls[value];
    console.log(modalImg.src)
    modalImg.style.width = 'auto';
    modalImg.style.height = '70%';
  })

  span.onclick = function() {
    modal.style.display = "none";
  }

  modal.onclick = function() {
    modal.style.display = "none";
  }

  chart.draw(data, options);

}

/* Style the Image Used to Trigger the Modal */

#myImg {
  border-radius: 5px;
  cursor: pointer;
  transition: 0.3s;
}

#myImg:hover {
  opacity: 0.7;
}


/* The Modal (background) */

.modal {
  display: none;
  /* Hidden by default */
  position: fixed;
  /* Stay in place */
  z-index: 1;
  /* Sit on top */
  padding-top: 100px;
  /* Location of the box */
  left: 0;
  top: 0;
  width: 100%;
  /* Full width */
  height: 100%;
  /* Full height */
  overflow: auto;
  /* Enable scroll if needed */
  background-color: rgba(255, 255, 255);
  /* Fallback color */
  background-color: rgba(255, 255, 255, 0.349);
  /* Black w/ opacity */
}


/* Modal Content (Image) */

.modal-content {
  margin: auto;
  display: block;
  width: 80%;
  max-width: 700px;
}


/* Caption of Modal Image (Image Text) - Same Width as the Image */

#caption {
  margin: auto;
  display: block;
  width: 80%;
  max-width: 700px;
  text-align: center;
  color: #ccc;
  padding: 10px 0;
  height: 150px;
}


/* Add Animation - Zoom in the Modal */

.modal-content,
#caption {
  animation-name: zoom;
  animation-duration: 0.6s;
}

@keyframes zoom {
  from {
    transform: scale(0)
  }
  to {
    transform: scale(1)
  }
}


/* The Close Button */

.close {
  position: absolute;
  top: 15px;
  right: 35px;
  color: #f1f1f1;
  font-size: 40px;
  font-weight: bold;
  transition: 0.3s;
}

.close:hover,
.close:focus {
  color: #bbb;
  text-decoration: none;
  cursor: pointer;
}


/* 100% Image Width on Smaller Screens */

@media only screen and (max-width: 700px) {
  .modal-content {
    width: 100%;
  }
}

.google-visualization-tooltip-item span { font-family: cursive !important; }

<!DOCTYPE html>
<html lang="en">

<head>
  <script type='text/javascript' src='https://www.gstatic.com/charts/loader.js'></script>
  <script type='text/javascript' src='https://www.google.com/jsapi'></script>
  <script src="mapa_prueba.js"></script>
  <link rel="stylesheet" href="mapa.css">

</head>

<body>

  <div id='map'></div>

  <div id="myModal" class="modal">

    <!-- The Close Button -->
    <span class="close" , id="close">&times;</span>

    <!-- Modal Content (The Image) -->
    <img class="modal-content" id="img01">

  </div>

</body>

</html>