It is not possible to delete the project on any platform. You can only archive it. The good news is that after the project has been archived, you can quickly restore it!
Here's what needs to be done:
Sign in to your account on the Web platform;
You will need to use the same credentials (email-password or social networks) as you use to log in to other platforms.
You'll get to the main screen with all your active projects listed. On the left-hand side of the screen you can see a menu. Find an Archive section and click it;
You've accessed the list of archived projects. Use the three dots at the corner of the project icon and use the Restore function;
Your restored project will become available on all platforms you're using.