Jekyll displays plain html instead proper content of gh-pages?

Hello!

I’ve just published my test gh-pages jekyll blog. Locally, everything looks good, when I put it finally on github pages and I try to access the blog it shows only HTML and looks pretty broken.

I’ve basically didn’t edit much - some text and added repository in _config.yml but the result is the same with or without this.

URL: https://slaffcheff.github.io/slaffcheff
repo: https://github.com/slaffcheff/slaffcheff

Can you please point my mistakes here?

Without doing absolutely NOTHING, the site started to work as expected. :\