Series.focusHighlight

<div id="chart"></div>
<script>
$("#chart").kendoChart({
  series: [{
    focusHighlight: {
      border: {
        color: "red",
        width: 3
      }
    },
    data: [10, 15, 20]
  }]
});
</script>

<div id="chart"></div>
<script>
$("#chart").kendoChart({
  seriesDefaults: {
    focusHighlight: {
      border: {
        color: 'blue',
        width: 3,
        dashType: 'dash',
        opacity: 0.5
      }
    }
  },
  series: [
    { type: "donut",  data: [3, 4] }
  ]
});
</script>