css style disappear when binding on ip instead of localhost

Hi, Another strange issue. I have a working and nice css style web page when burpui/gunicorn is bind on localhost and that I do an ssh tunel to reach the service. But if I bind gunicorn/burpui on an ip or 0.0.0.0, I can access the application but there are no css style at all, all is blank. I can't figure out why I have that.. If you have an advice it will be very appreciated! Thanks!