Update colors

lib/views/last_heard_view.dart

@@ -150,14 +150,14 @@ class _LastHeardItemTile extends StatelessWidget {
 
   const _LastHeardItemTile({required this.item});
 
-  Color _getEventColor() {
+  Color _getEventColor(BuildContext context) {
     switch (item.event) {
       case 'Session-Start':
         return Colors.green;
       case 'Session-Stop':
         return Colors.red;
       default:
-        return Colors.blue;
+        return Theme.of(context).colorScheme.primary;
     }
   }
 
@@ -174,7 +174,7 @@ class _LastHeardItemTile extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final eventColor = _getEventColor();
+    final eventColor = _getEventColor(context);
 
     return Card(
       margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),