I'm developing a Shiny app in Python and have created a heatmap that’s close to what I want.

However, instead of squares, I’d like each cell to be a square that contains a circle similar to the example below.

Here’s the relevant part of my Highcharts heatmap and its output:

        options = {
            'chart': {
                #'type': 'heatmap',
                'plotBorderWidth': 1,
                'width': 1500,
                'height': 800,
            },
            'title': {'text': postes},
            'xAxis': {
                'categories': categories_x,
                'title': {'text': ''}
            },
            'yAxis': {
                'categories': categories_y,
                'title': {'text': ''},
                'reversed': True,
                'labels': {'useHTML': True}
            },
            'legend': {'enabled': False},
            'series': [
                {
                    'type': 'heatmap',
                    'name': 'État EVT',
                    #'borderWidth': 1,
                    #'borderColor': 'black',
                    'data': heatmap_data,
                    'dataLabels': {'enabled': False}
                },
                {
                    'type': 'scatter',
                    'name': 'Alertes',
                    'data': icons_to_add,
                    'marker': {
                        'symbol': 'url(https://cdn-icons-png.flaticon.com/512/80/80795.png)',
                        'width': 20,
                        'height': 20
                    },
                    'enableMouseTracking': False
                }
            ],
            'boost': {'enabled': True},
        }
        plot_lines = []
        for i in range(len(categories_y) - 1):
            plot_lines.append({
                'color': '#cccccc',
                'width': 1,
                'value': i + 0.5,
                'zIndex': 5
            })

        options['yAxis']['plotLines'] = plot_lines
        options_json = json.dumps(options, ensure_ascii=False)

#### OUTPUT
@output
@render.ui
def hc_container_heatmap():
    options_json, dict_lien_ged_json, _, styled_df = donnees_compilees()
    return ui.HTML(f"""
        

        
    """)

And here's what I'm trying to achieve :

Is there a way to modify the Highcharts (or similar) configuration to achieve the look above?
Or, is there a better approach to render a graph with the same dataframe and integration within Shiny for Python?