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

# Themes, localization, and RTL

> Configure deterministic themes, locale-aware formatting, time zones, currency, and text direction.

Both renderers accept the same `RendererOptions` object.

```tsx theme={null}
<RUIRenderer
  options={{
    theme: "system",
    locale: "ar-EG",
    currency: "EGP",
    timeZone: "Africa/Cairo",
    direction: "rtl",
  }}
>
  {source}
</RUIRenderer>
```

| Option                 | Values/default                                    |
| ---------------------- | ------------------------------------------------- |
| `theme`                | `light`, `dark`, `system`; default `system`       |
| `locale`               | Canonical BCP 47 locale; default `en-US`          |
| `currency`             | ISO 4217 code; default `USD`                      |
| `timeZone`             | IANA time zone; default `UTC`                     |
| `direction`            | `ltr`, `rtl`, `auto`; default `auto`              |
| `externalLinkBehavior` | `confirm`, `direct`; default `confirm`            |
| `resourceTiming`       | `progressive`, `committed`, `manual`; progressive |

Options are validated, canonicalized, frozen, and exposed to custom components.
Invalid locale, currency, time zone, or enum values throw an option-specific
error.

For server rendering, pass identical explicit options on server and client to
avoid hydration differences. System theme uses CSS media queries rather than a
JavaScript listener. Portaled controls inherit language, direction, and theme
context. Chart geometry remains LTR for predictable coordinates while labels,
legends, tooltips, tables, and surrounding content follow the surface direction.