NamelessMC

When i change a color in my theme (Rapid) in Rapid/css/custom.css

then i will NOT update on the site what ever i do :( Can someone help me?

And if i change a picture i won't update to :(

Your browser might be caching the CSS, so try pressing Ctrl+F5.

Also, if you use something like Cloudflare, it might be caching the CSS too. In Cloudflare for example, there is a Caching tab where you can purge your website's cache.

I found the problem i had the 404 file from v1 i don't know why? 

No idea what happened there, glad you found the problem though!