Highchart vertical and horizontal scrollbar

I have dependency information that I would like to show on a web page using Highcharts. I chose Treegraph chart as I think it’s more suitable for what I need it for. This is the link to a demo https://www.highcharts.com/demo/highcharts/treegraph-chart.

The issue I have and I couldn’t overcome on my own is that when there are lots of branches and Leaves then the whole graph will get squeezed to show everything in one view. jsfiddle for code below is available in the link above.

Highcharts.chart('container', {
    chart: {
        spacingBottom: 30,
        marginRight: 120,
        height: 1200,
        scrollablePlotArea: {
            minWidth: 1500, // Set minimum width for horizontal scrolling
            minHeight: 1200 // Set minimum height for vertical scrolling
        }
    },
    title: {
        text: 'Phylogenetic language tree'
    },
    series: [
        {
            type: 'treegraph',
            keys: ['parent', 'id', 'level', 'color'], // Add color to keys
            clip: false,
            data: [
                [undefined, 'Proto Indo-European'],
                ['Proto Indo-European', 'Balto-Slavic'],
                ['Proto Indo-European', 'Germanic'],
                ['Proto Indo-European', 'Celtic'],
                ['Proto Indo-European', 'Italic'],
                ['Proto Indo-European', 'Hellenic'],
                ['Proto Indo-European', 'Anatolian'],
                ['Proto Indo-European', 'Indo-Iranian'],
                ['Proto Indo-European', 'Tocharian'],
                ['Indo-Iranian', 'Dardic'],
                ['Indo-Iranian', 'Indic'],
                ['Indo-Iranian', 'Iranian'],
                ['Iranian', 'Old Persian'],
                ['Old Persian', 'Middle Persian'],
                ['Indic', 'Sanskrit'],
                ['Italic', 'Osco-Umbrian'],
                ['Italic', 'Latino-Faliscan'],
                ['Latino-Faliscan', 'Latin'],
                ['Celtic', 'Brythonic'],
                ['Celtic', 'Goidelic'],
                ['Germanic', 'North Germanic'],
                ['Germanic', 'West Germanic'],
                ['Germanic', 'East Germanic'],
                ['North Germanic', 'Old Norse'],
                ['North Germanic', 'Old Swedish'],
                ['North Germanic', 'Old Danish'],
                ['West Germanic', 'Old English'],
                ['West Germanic', 'Old Frisian'],
                ['West Germanic', 'Old Dutch'],
                ['West Germanic', 'Old Low German'],
                ['West Germanic', 'Old High German'],
                ['Old Norse', 'Old Icelandic'],
                ['Old Norse', 'Old Norwegian'],
                ['Old Swedish', 'Middle Swedish'],
                ['Old Danish', 'Middle Danish'],
                ['Old English', 'Middle English'],
                ['Old Dutch', 'Middle Dutch'],
                ['Old Low German', 'Middle Low German'],
                ['Old High German', 'Middle High German'],
                ['Balto-Slavic', 'Baltic'],
                ['Balto-Slavic', 'Slavic'],
                ['Slavic', 'East Slavic'],
                ['Slavic', 'West Slavic'],
                ['Slavic', 'South Slavic'],
                ['Polish', 'POLISH2'],
                ['PPPPPPPPP1', 'QQQQQQQQQ'],
                // Leaves:
                ['Proto Indo-European', 'Phrygian', 6],
                ['Proto Indo-European', 'Armenian', 6],
                ['Proto Indo-European', 'Albanian', 6],
                ['Proto Indo-European', 'Thracian', 6],
                ['Tocharian', 'Tocharian A', 6],
                ['Tocharian', 'Tocharian B', 6],
                ['Anatolian', 'Hittite', 6],
                ['Anatolian', 'Palaic', 6],
                ['Anatolian', 'Luwic', 6],
                ['Anatolian', 'Lydian', 6],
                ['Iranian', 'Balochi', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Kurdish', 6],
                ['Iranian', 'Pashto', 6],
                ['Iranian', 'Sogdian', 6],
                ['Old Persian', 'Pahlavi', 6],
                ['Middle Persian', 'Persian', 6],
                ['Hellenic', 'Greek', 6],
                ['Dardic', 'Dard', 6],
                ['Sanskrit', 'Sindhi', 6],
                ['Sanskrit', 'Romani', 6],
                ['Sanskrit', 'Urdu', 6],
                ['Sanskrit', 'Hindi', 6],
                ['Sanskrit', 'Bihari', 6],
                ['Sanskrit', 'Assamese', 6],
                ['Sanskrit', 'Bengali', 6],
                ['Sanskrit', 'Marathi', 6],
                ['Sanskrit', 'Gujarati', 6],
                ['Sanskrit', 'Punjabi', 6],
                ['Sanskrit', 'Sinhalese', 6],
                ['Osco-Umbrian', 'Umbrian', 6],
                ['Osco-Umbrian', 'Oscan', 6],
                ['Latino-Faliscan', 'Faliscan', 6],
                ['Latin', 'Portugese', 6],
                ['Latin', 'Spanish', 6],
                ['Latin', 'French', 6],
                ['Latin', 'Romanian', 6],
                ['Latin', 'Italian', 6],
                ['Latin', 'Catalan', 6],
                ['Latin', 'Franco-Provençal', 6],
                ['Latin', 'Rhaeto-Romance', 6],
                ['Brythonic', 'Welsh', 6],
                ['Brythonic', 'Breton', 6],
                ['Brythonic', 'Cornish', 6],
                ['Brythonic', 'Cuymbric', 6],
                ['Goidelic', 'Modern Irish', 6],
                ['Goidelic', 'Scottish Gaelic', 6],
                ['Goidelic', 'Manx', 6],
                ['East Germanic', 'Gothic', 6],
                ['Middle Low German', 'Low German', 6],
                ['Middle High German', '(High) German', 6],
                ['Middle High German', 'Yiddish', 6],
                ['Middle English', 'English', 6],
                ['Middle Dutch', 'Hollandic', 6],
                ['Middle Dutch', 'Flemish', 6],
                ['Middle Dutch', 'Dutch', 6],
                ['Middle Dutch', 'Limburgish', 6],
                ['Middle Dutch', 'Brabantian', 6],
                ['Middle Dutch', 'Rhinelandic', 6],
                ['Old Frisian', 'Frisian', 6],
                ['Middle Danish', 'Danish', 6],
                ['Middle Swedish', 'Swedish', 6],
                ['Old Norwegian', 'Norwegian', 6],
                ['Old Norse', 'Faroese', 6],
                ['Old Icelandic', 'Icelandic', 6],
                ['Baltic', 'Old Prussian', 6],
                ['Baltic', 'Lithuanian', 6],
                ['Baltic', 'Latvian', 6],
                ['West Slavic', 'Polish', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['POLISH2', 'PPPPPPPPP1', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['POLISH2', 'PPPPPPPPP', 6],
                ['QQQQQQQQQ', '_=========_', 6],
                
                ['West Slavic', 'Slovak', 6],
                ['West Slavic', 'Czech', 6],
                ['West Slavic', 'Wendish', 6],
                ['East Slavic', 'Bulgarian', 6],
                ['East Slavic', 'Old Church Slavonic', 6],
                ['East Slavic', 'Macedonian', 6],
                ['East Slavic', 'Serbo-Croatian', 6],
                ['East Slavic', 'Slovene', 6],
                ['South Slavic', 'Russian', 6],
                ['South Slavic', 'Ukrainian', 6],
                ['South Slavic', 'Belarusian', 6],
                ['South Slavic', 'Rusyn', 6]
            ],
            marker: {
                symbol: 'circle',
                radius: 6,
                fillColor: '#ffffff',
                lineWidth: 3
            },
            dataLabels: {
                align: 'left',
                pointFormat: '{point.id}',
                style: {
                    color: '#000000',
                    textOutline: '3px #ffffff',
                    whiteSpace: 'nowrap'
                },
                x: 24,
                crop: false,
                overflow: 'none'
            },
            levels: [
                {
                    level: 1,
                    levelIsConstant: false,
                    colorByPoint: true
                },
                {
                    level: 2,
                    colorVariation: {
                        key: 'brightness',
                        to: -0.5
                    }
                },
                {
                    level: 3,
                    colorVariation: {
                        key: 'brightness',
                        to: 0.5
                    }
                },
                {
                    level: 6,
                    dataLabels: {
                        x: 10
                    },
                    marker: {
                        radius: 4
                    }
                }
            ]
        }
    ]
});


document.getElementById('container').style.overflow = 'auto';
document.getElementById('container').style.width = '100%';
document.getElementById('container').style.height = '800px';

How can I avoid the squeezing and add like a vertical and horizontal scrollbar? and as the graph grow vertically or horizontally instead of putting stuff on one another, grow the graph and add scrollbars(or maybe the ability to move the graph by dragging the graph).

I have been stuck on this for two days and it seems that I cannot figure it out on my own. I would appreciate any help. I’m not a web developer or a UI designer so please forgive any obvious thing that I might have missed.

Thanks