Updated line 122 with: marker=dict(size=10, color='#ff0000', symbol='circle'), # Red marker

app.py

@@ -119,7 +119,7 @@ def main():
         y=[hof[0][1]],
         z=[hof[0].fitness.values[0]],
         mode='markers',
-        marker=dict(size=10, color='#ffffff', symbol='circle'),  # White marker
+        marker=dict(size=10, color='#ff0000', symbol='circle'),  # Red marker
         name='Best Individual'
     )
     data.append(trace_best)