Hi,
I’m not able to log-in with the given details to cross-check, but I’m guessing this is very likely due to caching.
Looking at your site source, I can’t see the media query strings on any of the asset files, so there is some kind of caching enabled there. In this case, after making changes I highly recommend clearing all layers of cache: page cache, assets cache, varnish cache, Cloudflare or any other CDN cache and also your browser cache. Then re-loading the front page by pressing CTRL + SHIFT + R should force your browser cache to reload as well.
I usually turn off all caches when making style related changes, as assets files like javascript and CSS are very often cached on multiple layers.