Within the navigation, bookdown only allows for 3 levels of headings. I am trying to create a book with at least 8 levels. It is very important for even the 8th level to be easily navigated to. I was thinking about solving this solution with a nested book. For example, you have your first book. Then within a page in your first book, you have a link that you click on, that takes you to your second book.
The issue is, since I am creating two books, I would have two index.Rmd files - which doesn't work, since both would be located in same location on github. It would also mean my website would have the same webaddress for two pages. Another issue is, I don't think that when searching in the first book, pages in the second book will show up.
What are some ways to solve the problem of needing more than 3 levels in navigation? Currently I was thinking about nested books but am having trouble figuring out how to do it.