websites for good newer themes for Linux Mint 22....

For Linux Mint 22.3 Cinnamon 64-bit, stick to Cinnamon / GTK themes. The 64-bit part does not matter much for themes; Cinnamon compatibility matters more.

Best places to look:

1. Cinnamon Spices — official Mint theme site
   Best first stop. You can also install many of these directly from System Settings → Themes → Add/Remove.
   (Cinnamon Spices)

2. GNOME-Look: Cinnamon Themes, sorted by latest
   Good for newer community themes. Check the comments/date before installing.
   (https://www.gnome-look.org/browse/)

3. OpenDesktop / Pling: Cinnamon themes
   Same ecosystem as GNOME-Look, often with very recent experimental themes.
   (www.opendesktop.org)

4. Linux Mint Cinnamon Spices GitHub repo
   Useful if you want to inspect source files, updates, or theme folders directly.
   (GitHub)

5. Individual GitHub theme projects
   Good modern-looking ones to search for: Orchis, WhiteSur, Catppuccin GTK, Qogir, Graphite, and Fluent. For example, Orchis lists GTK/Cinnamon-related fixes, and WhiteSur is available through Cinnamon Spices as well.
   (GitHub)

My recommendation: start with Cinnamon Spices for stable themes, then use GNOME-Look sorted by “Latest” when you want newer or more experimental designs. For Mint 22.3 / Cinnamon 6.6, avoid very old themes unless recent comments confirm they still work.