<script src="https://code.highcharts.com/highcharts.js"></script>

<div id="container" style="height: 400px"></div>

Highcharts.chart('container', {
  chart: {
    type: 'spline'
  },
  title: {
    text: "Applying dash styles to line series"
  },

  legend: {
    symbolWidth: 80
  },

  plotOptions: {
    series: {
      color: '#000000'
    }
  },

  series: [{
    data: [1, 3, 2, 4, 5, 4, 6, 2, 3, 5, 6],
    dashStyle: 'longdash'
  }, {
    data: [2, 4, 1, 3, 4, 2, 9, 1, 2, 3, 4, 5],
    dashStyle: 'shortdot'
  }]
});