Update app.py

app.py

@@ -603,12 +603,18 @@ def main():
                     
                     # 操作按钮
                     col1, col2, col3, col4 = st.columns(4)
-                    
+
+
+                    if isinstance(topic, list):
+                        topic_str = "_".join(str(x).strip().replace(' ', '_') for x in topic if x)
+                    else:
+                        topic_str = str(topic)
+
                     with col1:
                         st.download_button(
                             label="📥 下载 MD",
                             data=final_blog,
-                            file_name=f"{topic.replace(' ', '_')}.md",
+                            file_name=f"{topic_str.replace(' ', '_')}.md",
                             mime="text/markdown",
                             use_container_width=True
                         )
@@ -626,7 +632,7 @@ def main():
                         st.download_button(
                             label="📥 下载 JSON",
                             data=json.dumps(export_data, ensure_ascii=False, indent=2),
-                            file_name=f"{topic.replace(' ', '_')}.json",
+                            file_name=f"{topic_str.replace(' ', '_')}.json",
                             mime="application/json",
                             use_container_width=True
                         )