Find out how to create CSS Counters for Feedback (depth 5)?

I would like so as to add numbering to my feedback, like this:

1. remark

1.1 reply to remark

1.2 reply to remark

1.2.1 reply to answer

2. remark

3. remark

I am an internet professional, so I typically perceive the best way to use CSS counters. What I have not seen is the best way to lengthen it for depth past 2. I’ve my WordPress feedback set to a depth of 5, and might’t determine the best way to write the CSS to show just like the above instance.

How do I lengthen the automated numbering for every new degree of depth?
Thanks!