When you search for your project in the Administrate screen, you are able to delete your project too. 

For your safety, projects are backed up every 24 hours. This means that if you accidentally delete your project in the morning, we can restore it within 15 days. Your copy will be from the backup made the previous day.

Not everything is backed up. Pictures and documents are not stored in backup – only the project data that contains project setup are, as well as user access and information.