* Update Electron info
There were changes made that remove the env variable:
https://github.com/electron/electron/issues/48001
* Clarify Electron versions
* Link to the electron section of the wiki
* Edit wording and link to the electron section of the wiki
* Add wiki based on mkdocs
* wording fixes
* fix github bg color on narrow
* Fix left sidebar section headers being bigger than pages
* fix hover accent
* fix list rendering on fractional layout
* fix videos
* fix automatic full links
* remove redundant commented css
* improve dark mode contrast
* update pygments for better child node coloring
* update logo
* remove blank lines
* add systemd language hint
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Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>
Ivan Molodetskikh