As a language model AI, I'll provide you with a simple example of how you can implement a game called "Little Anna's Pet Care" using JavaScript within a single HTML file. Please note that this is just a basic example, and you can further expand and enhance the game based on your requirements.
Little Anna's Pet Care
In this example, the game is displayed on a canvas element. The game loop is responsible for updating the game logic and rendering the game objects. The `clearCanvas` function clears the canvas for each frame, `updateScore` function updates and displays the score, `movePets` function handles the movement of pets, and `drawPets` function displays the pets on the canvas using pictograms or any other graphical representations you want to use.
You can further extend this code by adding custom game logic, additional features, levels, and improve the visual elements based on your requirements.