---
name: apply_theme
kind: function
lang: ts
domain: ui
version: "1.0.0"
purity: impure
signature: "applyTheme(theme: Theme): void"
description: "Inyecta un tema como CSS variables en document.documentElement. Maneja clase dark automáticamente. Mapea 40 tokens semánticos."
tags: [theme, css-variables, apply, runtime, ui]
uses_functions: []
uses_types: [ThemeConfig_ts_ui]
returns: []
returns_optional: false
error_type: "error_go_core"
imports: []
tested: false
tests: []
test_file_path: ""
file_path: "frontend/functions/ui/apply_theme.tsx"
source_repo: "https://gitea-dgg044oo04woo4ggcsws4gk0.organic-machine.com/Bl4cksmith/Frontend_Library"
source_license: "MIT"
source_file: "frontend/src/hooks/use-theme.tsx"
---

## Ejemplo

```typescript
import { applyTheme } from './apply_theme'

applyTheme({
  name: 'dark',
  label: 'Oscuro',
  colors: themeConfigToColors(darkThemeConfig)
})
```

## Notas

Función impura (modifica el DOM). Mapea cada key de ThemeColors a una CSS variable. Temas oscuros (dark, midnight, sunset) añaden clase `dark` al root.