> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zerotwo.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Theme & Language

> Customize ZeroTwo's appearance and interface language.

ZeroTwo's appearance and language settings are found in **Settings → Personalization**. Changes take effect immediately and persist across devices when you're logged in.

## Theme

Control whether ZeroTwo uses a light or dark color scheme.

**Settings → Personalization → Theme**

| Option     | Behavior                                                                                |
| ---------- | --------------------------------------------------------------------------------------- |
| **Light**  | Always uses the light theme regardless of your OS setting                               |
| **Dark**   | Always uses the dark theme regardless of your OS setting                                |
| **System** | Follows your operating system's appearance preference (auto-switches when your OS does) |

Changes apply immediately — no page reload needed.

<Tip>
  Use **System** if you switch between light and dark mode on your device throughout the day. ZeroTwo will follow along automatically.
</Tip>

## Language

ZeroTwo's interface and responses can be set to any of 11 supported languages.

**Settings → Personalization → Language**

| Language             | Code | RTL Layout?    |
| -------------------- | ---- | -------------- |
| English              | en   | No             |
| Spanish              | es   | No             |
| French               | fr   | No             |
| German               | de   | No             |
| Portuguese           | pt   | No             |
| Russian              | ru   | No             |
| Arabic               | ar   | Yes — full RTL |
| Hebrew               | he   | Yes — full RTL |
| Hindi                | hi   | No             |
| Japanese             | ja   | No             |
| Chinese (Simplified) | zh   | No             |

### What language affects

Setting a language changes:

* **ZeroTwo's interface text** — menus, labels, buttons, and system messages render in the selected language
* **ZeroTwo's default response language** — when you write in the interface language, ZeroTwo responds in that language

### RTL support

Arabic and Hebrew trigger full **right-to-left** layout mode throughout the ZeroTwo interface. Text alignment, navigation direction, and UI element positioning all adapt to RTL conventions.

### Writing in a different language than your setting

If you write a message in a language different from your interface language, ZeroTwo will typically respond in the language you wrote in. For example, if your interface is set to English but you write in French, ZeroTwo will respond in French.

To always respond in a specific language regardless of what you write in, add a Custom Instruction: **Settings → Personalization → Custom Instructions → Field 2**, e.g., "Always respond in English, even if I write in another language."

## Persistence

Both theme and language settings:

* Take effect immediately
* Persist when you log out and back in
* Sync across devices — set it once on any device and it applies everywhere you're logged into ZeroTwo