export interface FontBinding {
    /** CSS custom property the font is exposed as (next/font's `variable`
     *  option, or geist's fixed names); null when only `.className` exists. */
    variable: string | null;
    family: string;
    /** The font's `.className`/`.variable` is attached to a JSX attribute AND
     *  the reference's SYMBOL is the font's own declaration — actually applied
     *  to markup, not merely imported, configured, referenced in dead code, or
     *  shadowed. */
    applied: boolean;
}
/** Tailwind's default sans stack — identical in v3's
 *  `tailwindcss/defaultTheme` fontFamily.sans and v4's default `--font-sans`
 *  theme value (tailwindcss.com/docs/font-family). */
export declare const TAILWIND_DEFAULT_SANS: readonly string[];
/** Font bindings declared IN the given source (conventionally the root
 *  layout — fonts wired through a separate module are invisible here and the
 *  derivation simply doesn't fire, leaving the slot to the model pass). */
export declare function layoutFontBindings(source: string): FontBinding[];
/** A config's `fontFamily.sans` read has THREE outcomes, and the difference
 *  is load-bearing: `{ declared: false }` (the located config declares no
 *  sans — other derivation rules may apply), `{ declared: true, entries }`
 *  (parsed), and `{ declared: true, entries: null }` (a config exists but
 *  its sans — or the config object itself — is unprovable: authoritative,
 *  fail CLOSED to the model stage, never fall through to a guess). */
export type TailwindSansRead = {
    declared: false;
} | {
    declared: true;
    entries: string[] | null;
};
/** The config's sans array, located STRUCTURALLY through the exported config
 *  object only — config root (theme fragment files), `theme.fontFamily`, or
 *  `theme.extend.fontFamily`. An unrelated object elsewhere in the file that
 *  happens to carry a fontFamily key is never read. */
export declare function tailwindConfigSansStack(config: string): TailwindSansRead;
export interface DerivedFontStack {
    /** Raw comma-joined stack — callers normalize (extract-theme's
     *  normalizeFontStack owns quoting canonicalization). */
    value: string;
    /** Provenance string for ThemeSummary.matched. */
    provenance: string;
}
export declare function deriveBodyFontStack(input: {
    layout: string | null;
    tailwindConfig: string | null;
    /** Concatenated gathered CSS — only used for the Tailwind v4 marker. */
    cssText: string;
    /** Resolve a CSS custom property from the gathered sheets (light scope). */
    resolveCssVar: (name: string) => string | null;
    /** Raw value of a CSS `--font-sans` declaration whose var() refs the exact
     *  read could not resolve from the sheets alone (next/font variables live
     *  in the layout, not the CSS). */
    cssFontSans?: string;
}): DerivedFontStack | null;
/** The mono family the body derivation deliberately filters OUT of its sans
 *  candidates. It used to be found and dropped on the floor, so a host that
 *  ships a real code font (geist's Geist Mono, `next/font`'s Geist_Mono) got
 *  the generic system stack back. Same two rules as the body read: a declared
 *  `--font-mono` wins, else the single applied mono binding. */
export declare function deriveMonoFontStack(input: {
    layout: string | null;
    resolveCssVar: (name: string) => string | null;
    /** Raw value of a CSS `--font-mono` declaration, when one is declared. */
    cssFontMono?: string;
}): DerivedFontStack | null;