Someone assisted me in installing Drupal with Docker on my Mac. (I am new to Drupal and it has been years since I last coded.) The site works fine. I would like to set up a custom theme, but when I open VS Code in the installation directory, there are only the following files: .env, .gitignore, docker-compose.yaml. I don’t see a theme directory or anything that I expected. The docker-compose.yaml file has this in it: