Bug fix: wrong number for nested titles in TOC; add number for mobile TOC

[loikein]

A screenshot of the bug can be found here: (I have already fixed it in the links)
Fix TOC numbering issue · Issue #3 · loikein/hugo-book

Cheers!

[loikein]

Hi @alex-shpak, would you like to review this PR? Thank you!

[alex-shpak]

Hi! Sorry for long response.
I'm checking your pr now, 2 questions:

1. do you have a markdown snippet that I can use to reproduce such output?
2. my gut feeling tells that #TableOfContents ul does not affect something, as previous selector covers as well

[loikein]

Hi Alex, thanks for replying.

My site repo before the fix take effect is here: https://github.com/loikein/wiki/tree/c561b0fd339017acfc4a95df60c1e111cabdf37a (with the theme as a submodule in the themes folder)
And the particular page in that screenshot is: https://github.com/loikein/wiki/blob/c561b0fd33/content/computer/software-usage/obsidian/index.md

The #TableOfContents ul, if my memory serves, was a quick way of capturing the mobile TOC without having to alter the style. Currently, the mobile TOC does not have numbers even when the numbered plugin was enabled.