We fixed a caching issue that could keep the Preview showing old CSS after you changed a cloud project. Cloudflare was telling browsers to keep some Preview stylesheets for too long, so a normal reload could bring back stale styles instead of the latest version from your project.
New Preview requests now respect the project server's cache headers, so CSS changes refresh normally.
If your browser already cached the old response, clear it once: open the affected project or folder, open the browser developer console, go to the Network tab, turn on Disable cache, and reload the page. After that one reload, the stale Preview cache is cleared and future updates should work normally.