Update app.py

app.py

@@ -74,6 +74,9 @@ st.markdown(
     .stPlotlyChart {
         display: block;
         margin: 0 auto;
+        border: 5px solid #001A6E; /* Border color for the plot */
+        border-radius: 10px; /* Rounded corners for the border */
+        padding: 5px;
     }
     /* Adjusting for full width without scrolling */
     .css-1lcbvhc {
@@ -219,7 +222,7 @@ with col2:
             name="Tangent Line"
         ))
 
-        # Update layout to show negative y-axis and white axes
+        # Update layout to include a white axis and styled border
         fig.update_layout(
             xaxis=dict(
                 title="x-axis",