HTML file:
This HTML file defines a basic card battle game. It includes JavaScript code enclosed in script tags. The game starts automatically by calling the `playTurn()` function. Each player has a castle with 1000 health points and a set of cards. During each turn, the current player chooses one card to attack the opponent's castle, and then the opponent attacks the player's castle with their own card. The game continues until one of the castles' health points reaches zero. The game displays a message indicating whether the player wins or loses.