I am trying to configure active admin 3.3.0 with my ruby on rails project. I am able to get the admin login page but unfortunately I am having some troble having the stylesheet not being applied as the image shows:

Here the steps I have followed

rails g active_admin:install
rails db:create
rails db:migrate
rails db:seed

bin/rails server -b 0.0.0.0 -p 3000

I see there is no manifest.js that in older project is there but I do not really know what to do, I am quite stuck :/

Thank to everyone in advance for any help!

EDIT 1

In my console i get this error from javascript

active_admin-1f4b319c.js:1 Uncaught SyntaxError: Cannot use import statement outside a module