Update app.py

app.py

@@ -365,7 +365,12 @@ def main():
     if "last_answered_question" not in st.session_state:
         st.session_state.last_answered_question = ""
 
-    st.header("Chat with MODTRAN Document 📄")
+    st.markdown("""
+        <h2>Chat with MODTRAN Documents 📄</h2>
+        <a href="https://drive.google.com/file/d/1XwPKpooLRhq9C1-ESXV3HiCnmJJxdN9-/view?usp=sharing" target="_blank" style="text-decoration: none; font-size: 0.9rem;">
+            View MODTRAN 6 User's Manual
+        </a>
+        """, unsafe_allow_html=True)
 
     # Inject custom CSS for chat bubbles
     st.markdown("""