You are trying to load the styles file incorrectly.
The system tries to load http://climb-loetschen.great-site.net/climb-loetschen.great-site.net/assets/css/styles.css, however the URL is http://climb-loetschen.great-site.net/assets/css/styles.css, so it won’t load.
Remove that second climb-loetschen.great-site.net and you should be good to go!