Update app.py

app.py

@@ -105,6 +105,13 @@ def detect_outliers(series):
     iqr = q3 - q1
     return ((series < (q1 - 1.5 * iqr)) | (series > (q3 + 1.5 * iqr))).sum()
 
+# Define app_mode for navigation
+app_mode = st.sidebar.selectbox(
+    "Select Page",
+    ["Data Upload", "Smart Cleaning", "Advanced EDA", "Model Training", "Insights", "Predictions", "Neural Network Studio"],
+    help="Choose the section to navigate to."
+)
+
 # --- Data Upload Page ---
 if app_mode == "Data Upload":
     st.title("📤 Smart Data Hub")