You can see in the video, there is a Cloudflare cache enabled on your site from your server as well, so you have to contact your hosting provider and ask to first flush/remove all sorts of server cache including Cloudflare and then disable it till you are in the development process.
And finally, you have to check it on your site after removing the browser cache, I am sure you will not face this issue anymore.
Note: I have not reverted back the original colors on your site of the header, so please revert or change it back now as per your requirements.
