The backend is ready.
there will be 2 main screens as well as standard login/logout activities
first is the product screen. Products listed here. They will come from Algolia API.
They can be added to lists. Then send the shopping list to the backend.
second is the user profile. here the user can see her lists.
the look and feel should be good. you are welcome to use a UI template.
it should be easy to read, maintain, and to add new features.