Handsontable example

HTML

<link rel="stylesheet" href="https://docs.handsontable.com/pro/bower_components/handsontable-pro/dist/handsontable.full.min.css">
<script src="https://docs.handsontable.com/pro/bower_components/handsontable-pro/dist/handsontable.full.min.js"></script>
<div>
  <div id="example1" class="hot handsontable htRowHeaders htColumnHeaders"></div>
</div>

CSS

body {
  font: 0.8em Helvetica;
}

.handsontable thead TR:nth-child(1) {
  font-size: 1.9em;
  color: #009688 !important;
  font-weight: bold;
}

.handsontable thead TR:nth-child(2) th {
  font-size: 1.7em;
  text-align: left;
}

.handsontable thead TR:nth-child(3) {
  font-size: 1.5em;
  font-weight: bold;
  text-align: right !important;
}

JavaScript

document.addEventListener("DOMContentLoaded", function() {

  var example1 = document.getElementById('example1');

  var hot = new Handsontable(example1, {
    data: Handsontable.helper.createSpreadsheetData(5, 10),
    colHeaders: true,
    rowHeaders: true,
    nestedHeaders: [
      ['A', {
        label: 'B',
        colspan: 8
      }, 'C'],
      ['D', {
        label: 'E',
        colspan: 4
      }, {
        label: 'F',
        colspan: 4
      }, 'G'],
      ['H', {
        label: 'I',
        colspan: 2
      }, {
        label: 'J',
        colspan: 2
      }, {
        label: 'K',
        colspan: 2
      }, {
        label: 'L',
        colspan: 2
      }, 'M'],
      ['N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W']
    ]
  });



});