Improve Documentation by having list of topics fixed on the left and table of contents on the right

Hey all,

I am using Django for a long time. One thing I feel we can improve is that the reading experience of the documentation. Especially when the page is very long. Two problems I can see

1. There is a table of contents on the right side, but it is not fixed and it doesn't follow the page. So, when the page is very long, keeping track of the topic is very very hard and it takes a mental leap to go back and navigate.
2. Also, on any page, you can only see only the previous topic and the next topic, not the whole content.

Below are some of the example documentation

https://getbootstrap.com/docs/5.1/getting-started/introduction/

https://vuejs.org/v2/guide/

https://docs.spring.io/spring-framework/docs/current/reference/html/core.html

https://tailwindcss.com/docs/configuration

I have done a search on the issues and found #239 is closed and #494 is still open from 2015. I am not blaming anyone honestly, I know being an open-source project, it is hard to prioritize things. I wanted to take the initiative and work on it.

I think the problem here is we need to migrate entirely from sphinx documentation, but unfortunately in the python community, there's no better alternative. Please suggest or point me in the direction of how can we achieve this.