Update app.py

app.py

@@ -699,12 +699,26 @@ else:
                     st.warning(err_msg)
                 else:
                     fig, ax = plt.subplots(figsize=(6, 5))
-                    sns.heatmap(corr_matrix, annot=True, fmt=".2f", cmap="coolwarm", center=0, ax=ax)
-                    ax.tick_params(axis='x', labelsize=9)
+
+                    mask = np.triu(np.ones_like(corr_matrix, dtype=bool))
+
+                    sns.heatmap(
+                        corr_matrix,
+                        mask=mask,
+                        cmap="coolwarm",
+                        annot=True,
+                        fmt=".2f",
+                        center=0,
+                        square=True,
+                        linewidths=0.5,
+                        cbar_kws={"shrink": 0.7},
+                        ax=ax
+                    )
+                    
+                    ax.tick_params(axis='x', labelrotation=45, labelsize=9)
                     ax.tick_params(axis='y', labelsize=9)
                     ax.set_xlabel("")
                     ax.set_ylabel("")
-                    country_fullname = country_mapping.get(selected_region, selected_region)
-                    title_str = f"{country_fullname} - {selected_commodity} ({start_year}–{end_year})"
-                    ax.set_title(title_str)
+                    ax.set_title(f"{country_mapping.get(selected_region, selected_region)} - {selected_commodity} ({start_year}–{end_year})", fontsize=12, pad=12)
+                    
                     st.pyplot(fig)