Halo

Node halos are controlled via the halo attribute.
          <!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <script src="../build/ogma.min.js"></script>
  <style>
    #graph-container { top: 0; bottom: 0; left: 0; right: 0; position: absolute; margin: 0; overflow: hidden; }
  </style>
</head>
<body>
  <div id="graph-container"></div>

<script>
'use strict';


var ogma = new Ogma({
  container: 'graph-container'
});

ogma.styles.addNodeRule({
  halo: {
    color: 'white',
    size: 20,
    strokeColor: '#EA5565'
  }
});

ogma.generate.random({
  nodes:20,
  edges:30
}).then( function (graph) {
  ogma.setGraph(graph);
  ogma.view.locateGraph();
});

ogma.setOptions({ backgroundColor: '#1E1D32'});



</script>
</body>
</html>