Actually, that's not right approach because we do not have any view like that available. So you would have to:
- Choose one of the view which has the layout you want at starting point. For this, I guess components/com_osmembership/view/categories/tmpl/default.php should be the starting point
- Implement the change you want there. You can use bootstrap accordion in Joomla core API to add accordion to the page. See code from administrator/components/com_osmembership/view/dashboard/tmpl/default.php as an example
- If you need to add any custom css to change the behavior, go to Membership Pro -> Configuration, look at Custom CSS tab and add the css code you want there
I am surprised not too many people have asked about this feature. It allows your clients to basically see all your plans on one page and not press back and forward on their browsers, especially since the extension doesnt give you a "BACK" button. This is especially useful on a smartphone screen.
Tuan, how can I ask for a customization of this sort?