update: same shape color on selection

app/lib/widgets/choropleth_map.dart

@@ -106,7 +106,7 @@ class _ChoroplethMapState extends State<ChoroplethMap> {
                 onSelectionChanged: (int index) {  // Shape selection behavior
                   setState(() {
                     selectedIndex = index;
-                    selectedColor = subdivisions[index].color.withOpacity(0.7);
+                    selectedColor = subdivisions[index].color;
                   });
                   widget.onSelectionChanged(selectedIndex);
                 },