Failing to display nice html / css and js forbidden

I am getting the following error when viewing RT and it looks like somewhat text file instead of nice display

Failed to load resource: the server responded with a status of 403 (Forbidden) aileron-squished-a53…5e5a8c4cc0a3ee1.css

Failed to load resource: the server responded with a status of 403 (Forbidden) squished-0be26945f74…f6838aec5d6fb463.js

Uncaught ReferenceError: jQuery is not defined rt.example.net/:38
at rt.example.net/:38

Uncaught ReferenceError: jQuery is not defined rt.example.net/:51
at rt.example.net/:51

Uncaught ReferenceError: jQuery is not defined rt.example.net/:125
at rt.example.net/:125

Failed to load resource: the server responded with a status of 403 (Forbidden) print.css

Failed to load resource: the server responded with a status of 403 (Forbidden) aileron-squished-a53…5e5a8c4cc0a3ee1.css

Failed to load resource: the server responded with a status of 403 (Forbidden) print.css

Any suggestion what is going on?

Thanks for your help!

I start RT like this /opt/rt4/local/plugins/RT-Extension-Nginx/sbin/rt-nginx-control start

And I am using 4.0.17 with mysql 5.5.54 and perl 5.16.3 on centos 7

The display looks exactly like it suppose to when start it as standalone like below

/opt/rt4/sbin/rt-server --port 8080