Update app.py

app.py

@@ -132,8 +132,9 @@ with chat_placeholder:
 </div>
         """
         st.markdown(div, unsafe_allow_html=True)
-
+if st.session_state.history:
     last_chat = st.session_state.history[-1]
+    
     div_start = f"""
 <div class="chat-row 
     {'' if last_chat.origin == 'ai' else 'row-reverse'}">