Fix bar chart y-axis scaling (rangemode=tozero)

app.py

@@ -295,6 +295,7 @@ if selected_view == "Strategy":
             xaxis_title="Fleet Size",
             yaxis_title="Extra Profit from Circular Model (EUR)",
             showlegend=False,
+            yaxis=dict(rangemode='tozero'),
         )
         st.plotly_chart(fig_advantage, use_container_width=True)
 
@@ -314,6 +315,7 @@ if selected_view == "Strategy":
             title="Products Needed to Serve Same Customers",
             xaxis_title="Fleet Size Target", yaxis_title="Products to Manufacture",
             barmode="group", legend=dict(orientation="h", yanchor="bottom", y=1.02),
+            yaxis=dict(rangemode='tozero'),
         )
         st.plotly_chart(fig_products, use_container_width=True)
 
@@ -361,6 +363,7 @@ if selected_view == "Strategy":
         fig_sens.update_layout(
             title="Profit Advantage by # of Cycles",
             xaxis_title="Number of Use Cycles", yaxis_title="Profit Advantage (EUR)",
+            yaxis=dict(rangemode='tozero'),
         )
         fig_sens.add_vline(x=max_cycles, line_dash="dash", line_color="blue",
                           annotation_text=f"Current: {max_cycles}")
@@ -376,6 +379,7 @@ if selected_view == "Strategy":
         fig_cost.update_layout(
             title="Cost Savings from Reuse",
             xaxis_title="Number of Use Cycles", yaxis_title="Cost Saved vs Linear (EUR)",
+            yaxis=dict(rangemode='tozero'),
         )
         st.plotly_chart(fig_cost, use_container_width=True)