```
**Explanation**
* The `` tag disables user scaling and sets the maximum scale to 1.
* `touch-action: none;` is applied to the `` to ensure touch interactions are handled by the script only.
* The chat area (`.chat`) is a scrollable flex container that holds message bubbles.
* Messages alternate sides (`left` or `right`) each time the user sends a new message.
* A simple auto‑reply mechanism adds a reply on the opposite side, creating a conversation feel.
* The input area uses standard click and keyboard events, which work seamlessly on both desktop and touch devices.