otstrap.min.js"></script>
    <script>
        Chart.pluginService.register({
            afterUpdate: function (chart) {
                if (chart.config.options.elements.center) {
                    var helpers = Chart.helpers;
                    var centerConfig = chart.config.options.elements.center;
                    var globalConfig = Chart.defaults.global;
                    var ctx = chart.chart.ctx;

                    var fontStyle = helpers.getValueOrDefault(centerConfig.fontStyle, globalCo