How can I change the distance between columns in highcharts?

I can't edit the distance between columns, I want to reduce it. How can I solve it?

for columns I write this:

    column: {
            maxPointWidth: 60,
            pointWidth: 15,
            marker: {
                enabled: true
            },
            borderWidth: 0, // distanza dall'asse x
            dataLabels: {
                crop: false,
                overflow: "none",
                enabled: true,
                x: 20,
                y: -30,
                rotation: 270,
                style: {
                    fontSize:'10px'
                }
            }
        }

Should I add something here?

https://jsfiddle.net/Maestro1508/s1afo046/2/

Chart