Several stylistic fixes

[codenyte]

• Typo/capitalization fixes
  • Github -> GitHub
  • Youtube -> YouTube
  • Webview -> WebView
  • OpenStreetMaps -> OpenStreetMap
  • etc.
• Use <code> tags instead of `
• New (2024) Signal logo
• Move the invert and invert2 classes from the style tag in index.html to style.css
  • Use index2 for the GrapheneOS logo and the macOS logo, replacing my previous workaround 00e9df1
• Fix links in top.js and bottom.js so they also work when clicked from a page in the old/ directory
  • This will not work when opening the website locally using the file:// prefix in your browser, it works correctly when served from a web server though. I used python3 -m http.server for quick and easy testing.
• Android comparison table:
  • Use vertical-align: middle; because it looks better and makes the   workaround obsolete
  • Better readability of anchor text when using dark mode

I hope I mentioned and adequately described all my changes. If you have further questions about any of my changes, don't hesitate to ask. I'm sorry for squashing everything into one commit, but otherwise the commit history would have been a complete mess.

[eylenburg]

Thank you very much!