The iOS Dark Mode Theme by @basnijholt and modified from @kalkih's Gist

With alternative background (backgrounds/homekit-bg-4.jpeg):

1. Add the following code to your configuration.yaml file (reboot required).

frontend:
  ... # your configuration.
  themes: !include_dir_merge_named themes
  ... # your configuration.

2. Add the following line to your lovelace-ui.yaml or use the RAW editor:

background: var(--background-image)

3. (Optional) change the background to a different one, see backgrounds/README.md.

1. Go to the Community Store.
2. Search for iOS Dark Mode.
3. Navigate to iOS Dark Mode theme.
4. Press Install.

Clone this repository in your existing (or create it) themes/ folder.

cd themes/
git clone https://github.com/basnijholt/lovelace-ios-dark-mode-theme.git

Or using submodules:

cd themes/
git submodule add https://github.com/basnijholt/lovelace-ios-dark-mode-theme.git