DataTable - how to update style (specifically font family and size)

You can change font family and size like this:

app = dash.Dash(__name__)

app.layout = dash_table.DataTable(
    id='table',
    columns=[{"name": i, "id": i} for i in df.columns],
    data=df.to_dict("rows"),
    style_cell={'fontSize':20, 'font-family':'sans-serif'}
)

if __name__ == '__main__':
    app.run_server(debug=True)