Changed my database from SQLite 3 to Posgresql. Why does my Ruby on Rails project no longer show any of my animations or CSS?

I'm a beginner coder and I'm trying to push my project (a Detective game with a noir setting) online to Heroku. Now, since you cannot use SQLite3 for Heroku, I had to change my project to PosgreSQL and precompile all of my assets. I have done so and my project comes out looking like a complete mess. Here is a video showing everything I have done:

https://www.youtube.com/watch?v=zQjkayzca7A&feature=youtu.be

The steps I have taken:

A - In my database.yml file, I changed my adapter from sqlite3 to postgresql, I also added an encoding: unicode line. I also changed my database names to custom names.

B - My gemfile was also changed, I changed my "sqlite3" gem to "pg"

C - Next I did a bundle install

D - Next, I added this into my terminal:

RAILS_ENV=production bundle exec rake assets:precompile

This precompiled all my assets, and then I followed up with this code:

git add public/assets git commit -m "vendor compiled assets"

E - Afterwards I commited my changes, created a Heroku repository, and successfully pushed to my repository. However, as you can see in my video, my project turned out nothing like it was supposed to. Any ideas?