import { BrandTheme } from '@fanfare-io/fanfare-sdk-core/theme';
/**
 * Builds CSS custom property values from a theme override.
 *
 * Only emits CSS vars for fields the customer explicitly configured plus any
 * vars derived from those (computed foregrounds, mirrored mutedForeground,
 * heading font fallback). Defaults for unset fields come from the SDK's CSS
 * layer (:root @theme + [data-fanfare-variant] selectors), so per-variant
 * defaults survive single-token overrides.
 *
 * Color semantics (aligned with messaging templates):
 * - surface: Outer/surrounding area (transparent by default)
 * - background: Main content area (white by default)
 *
 * Note: border is intentionally NOT mirrored from `muted` — see the comment
 * inside the muted branch.
 */
export declare function buildThemeCssVars(theme: BrandTheme): Record<string, string>;