Update app.py

app.py

@@ -698,6 +698,7 @@ CRITICAL RULES:
 4.  **JSON SERIALIZATION:** Before adding data to your final dictionary for JSON conversion, you MUST convert any pandas-specific types (like `int64`) to standard Python types using `.item()` for single values or `.tolist()` for lists.
 5.  **SINGLE JSON OUTPUT:** Print exactly ONE JSON object at the end of your script. Do not print debug statements or multiple JSON objects.
 6.  **VALID JSON STRUCTURE:** The output MUST be a dictionary/object, not an array or primitive value.
+7.  **SAFE DATA JOINING:** When joining/merging dataframes or looking up values across dataframes, ALWAYS check if matches exist before accessing with `.iloc[0]`. Use `.merge()` with `how='left'` or check `len(filtered_df) > 0` before accessing rows. Never assume keys will match exactly between dataframes.
 
 --- USER'S SCENARIO ---
 {user_scenario}
@@ -941,8 +942,8 @@ SLEEK_CSS = """
 
 .right .tabs { height: 100%; display: flex; flex-direction: column; }
 .right .tabitem { flex: 1; display: flex; flex-direction: column; overflow: hidden; }
-#chatbot_container { flex: 1; min-height: 700px; max-height: calc(100vh - 150px); overflow-y: auto; }
-#chatbot_container > * { min-height: 700px; }
+#chatbot_container { flex: 1; min-height: 600px; max-height: calc(100vh - 150px); overflow-y: auto; }
+#chatbot_container > * { min-height: 600px; }
 
 .hr { height: 1px; background: #16203b; margin: 10px 0; }
 .voice-hint { font-size: 12px; color:#9fb0cc; margin-top: 4px; }