improving demo text

app.py

@@ -92,8 +92,9 @@ option = st.selectbox(
     "select template grids",
     grids,
 )
-x = st.text_area('grid', value=grids[option], height=300)
+x = st.text_area('You can edit the grid, every format is accepted. Empty cell can be designed by `0` or by `.`', value=grids[option], height=300)
 
+st.markdown('### Initial grid')
 tensor_grid, df_styler = build_grid_and_display(str_to_row_col_grid(x))
 # st.table(df_styler)
 # st.dataframe(df_styler)
@@ -102,13 +103,15 @@ html = df_styler.to_html(escape=False, index=False)
 st.html(html)
 st.markdown('''
             ## Checking the number of solutions 
-            (with backtracking algorithm)
-            must be equal 1
+            (with classical backtracking algorithm).
+            
+            Number of solutions must be one to trigger the grid resolution.
             ''')
 n_sol = get_grid_number_soluce(str_to_row_col_grid(x))
 
 st.markdown(f"number of solution: {'>2' if n_sol==2 else n_sol}")
 if n_sol==1:
+    st.markdown('## Predicting grid step by step')
     new_X = model.predict(tensor_grid)
     X_sum= new_X.sum()
     st.html(display_as_dataframe(new_X).to_html(escape=False, index=False))