Hello Leszek
Unfortunately, it is not possible. Joomla only allow assigning template base on menu item, not base on URL
So it is not possible to use a specific template for detail view of an event
There is a workaround. That's create menu item to link to event details of each event, then assign template to these menu items
However, it won't be doable if you have many events in your system
Tuan
