{"type":"rich","version":"1.0","title":"美国内战原因","description":"学生将关于美国内战原因的描述拖放到“北方立场”或“南方立场”分类中","author_name":"Padlet TA","thumbnail_url":"https://arcade.padlet.com/open-graph/social-preview-image.png?timestamp=1767922019301&hashid=3yjNAXvRr4","html":"<iframe src=\"https://arcade.padlet.com/embed/3yjNAXvRr4\" width=\"720\" height=\"480\" frameborder=\"0\" allowfullscreen></iframe>","width":720,"height":480,"provider_name":"Padlet Arcade","provider_url":"https://arcade.padlet.com"}