Downloads: Refine prior commit

[TheTechnician27]

Refines #445.

• Nightly documentation link now the correct amber rather than mac and cheese blue like it was accidentally left as due to a bug on my part.
• Slightly refined the stable documentation link color to make it more readable and in-line with the other blues.
• Made it so the header icons actually work.
• Removed useless global CSS classes and used Tailwind built-ins instead for better icon header alignment.
• Changed 'MacOS' to 'macOS'.
• Changed the download button order from Windows -> Linux -> macOS to Windows -> macOS -> Linux.
  • I speculate this order was a byproduct of when macOS was an experimental option.
  • The typical ordering of the three major OSes is "Windows, macOS, Linux".
  • The big thing, though, is that Linux has two releases for both Stable and Nightly. Windows only has this in one, and it's far and away the largest portion of our userbase. macOS here stands out a lot better and doesn't get swamped by four entire releases in Stable and three in Nightly.