Cannot Access Site After Let's Encrypt

I was setting up a testbed at

The demo apps worked fine. Then I tried to setup Let’s Encrypt. Now the site kind of loads, but none of the assets are visible.

Issue similar to this Shinyproxy (in docker) and auto nginx proxy

Just wanted to know where I could look to solve this issue.

I have an application.yml file with the following bit

Docker configuration

  cert-path: /etc/letsencrypt/live/
  url: http://localhost:2375
  port-range-start: 20000