> ISPO SDK documentation. [HTML](https://ispo.ai/docs/types/core.ThemeFrame.html) · [Documentation index](https://ispo.ai/docs/llms.txt)

# Type Alias ThemeFrame

```typescript
ThemeFrame: FrameBase<"theme"> & {
    css?: string | null;
    hostDevBuild?: boolean;
    name: ThemeName;
    themeId?: string;
}
```

Types: [FrameBase](core.Supporting_types.FrameBase.md), [ThemeName](core.Supporting_types.ThemeName.md)

#### Type Declaration

*   ##### `Optional`css?: string | null
    
*   ##### `Optional`hostDevBuild?: boolean
    
    True when the HOST is an unpackaged dev build (`!app.isPackaged`) — the host-build flavor, NOT this project's §3.18 effective bundle mode. Rides the theme frame because that is the hello-reply bootstrap seam. Omitted by an older host; consumers treat absence as "unknown", not false.
    
*   ##### name: [ThemeName](core.Supporting_types.ThemeName.md)
    
*   ##### `Optional`themeId?: string