问如何使用JS在外部点击时显示不同颜色的地理地图

EN

options['colors'] = [0xbaecc7, 0x3bc75f]; // light to dark green

google.setOnLoadCallback(drawMap);

function drawGoalsMap() {
            var options = {};
            options['dataMode'] = 'regions';
            options['region'] = 'world';
            options['colors'] = [0xbaecc7, 0x3bc75f]; // light to dark green
            options['width'] = '900px'; 
            options['height'] = '400px';

            var data = new google.visualization.DataTable();
            data.addRows(6);
            data.addColumn('string', 'Country');
            data.addColumn('number', 'Messages');
            data.setValue(0, 0, 'Germany');
            data.setValue(0, 1, 200);
            data.setValue(1, 0, 'United States');
            data.setValue(1, 1, 300);
            data.setValue(2, 0, 'Brazil');
            data.setValue(2, 1, 400);
            data.setValue(3, 0, 'Canada');
            data.setValue(3, 1, 500);
            data.setValue(4, 0, 'France');
            data.setValue(4, 1, 600);
            data.setValue(5, 0, 'RU');
            data.setValue(5, 1, 700);

            var container = document.getElementById('map_canvas');
            var geomap = new google.visualization.GeoMap(container);
            geomap.draw(data, options);

            google.visualization.events.addListener(geomap, 'regionClick', 
                function(e) {
                                var countryCode = e['region'];
                                DrillDown(countryCode);
                            }
            );

        };