Update app.py

app.py

@@ -47,7 +47,7 @@ nav_html += "</div><br><br><br>"
 st.markdown(nav_html, unsafe_allow_html=True)
 
 # Get selected subject from query params
-subject = st.experimental_get_query_params().get("nav", ["Architecture"])[0]
+subject = st.query_params.get("nav", ["Architecture"])[0]
 
 # Load and display content
 if subject in subjects: