It is definitely because of cache, I see an older cached, minified stylesheet loaded. I suggest disabling the cache for the time of development and changes. Make sure to clear all layers of caches (page, minify, asset, cloudflare, CDN etc.., then reload the page by hitting CTRL + SHIFT + R), update media query strings. Some cache solutions leverage 2-3 day expiry times, and can be extremely hard to clear them. The search cannot affect the cache unfortunately, it sends an update request, but the rest is up to the cache solution.
I have enabled this option for now: https://i.imgur.com/TrNeLSQ.png
This will oad the CSS files separately from the cache. I still however recommend properly clearing the site cache.
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