title: How to display both horizontal and vertical grid lines in google chart
body: <pre><code>  google.setOnLoadCallback(drawChart);
  
    function drawChart() {
        var data = google.visualization.arrayToDataTable([
            ['Year', 'Sales', 'Expenses'],
            ['2004', 1000, 400],
            ['2005', 1170, 460],
            ['2006', 660, 1120],
            ['2007', 1030, 540]
        ]);
  
        var options = {
            title: 'Company Performance',
        };
  
        var chart = new google.visualization.LineChart(document.getElementById('chart_div'));
  
        chart.draw(data, options);
    }
  </code></pre>
  
  <p>this code only shows horizontal grid line, I want to show vertical lines also.</p>