# script
Return an inline script that restores saved preferences before the first paint.
`script` comes from [`defineConfig`](/docs/api/core/defineConfig). Calling it is pure and safe during server rendering. The returned source runs in the browser, reads the record that [`appearance`](/docs/api/core/defineConfig/appearance) saves, and applies it to `document.documentElement`.
```tsx title="Document.tsx"
import type { ReactNode } from 'react'
import { script } from './zyzz.config.js'
export function Document(props: Document.Props) {
return (
{/* Runs synchronously before the body renders */}
{props.children}
)
}
export declare namespace Document {
type Props = { children: ReactNode }
}
```
## Signature
```ts
// HTML-safe JavaScript source
script()
```
## Returns
### source
* **Type:** `string`
JavaScript for an inline, synchronous ``, quotes, and Unicode line separators, and never evaluates saved strings. A content security policy can allow it with a nonce on the script element or a hash of the exact source.
```tsx
// The nonce comes from the response's content security policy
```
React markup can set `suppressHydrationWarning` on ``, since the script changes its classes before hydration.
## React Native
The script runs against the document, so native apps have no counterpart. A native app loads its saved preference into application state and passes it to the native [`Provider`](/docs/api/react-native/Provider), as [Native Themes](/docs/guides/native/themes) shows.