---
title: "useTheme"
description: "useTheme() returns 'light' or 'dark' and re-renders with the host theme. It is read-only: apps adapt to the workspace theme; they do not mutate it."
url: "https://sotaagents.ai/manual/developer-guide/use-theme"
generated_by: "sotaagents-ldp"
docs_index: "https://sotaagents.ai/manual/llms.txt"
locale: "en"
---

# useTheme

`useTheme()` returns `'light'` or `'dark'` and re-renders with the host theme. It is read-only: apps adapt to the workspace theme; they do not mutate it.

TSX

```
import { useTheme } from '@sota/platform';

export function Preview() {
  const theme = useTheme();
  return <div className="preview" data-theme={theme}>Preview</div>;
}
```

Code

```css
.preview {
  color: var(--foreground);
  background: var(--background);
}

.preview[data-theme='dark'] .diagram {
  filter: brightness(0.9);
}
```

Prefer the shared design tokens inherited by native surfaces. Use the hook only when behavior or non-CSS assets genuinely differ by theme.