import { type ColorTokens } from "../../style/tokens.js";
export type Density = "sparse" | "default" | "dense";
export type Prominence = "subtle" | "default" | "vivid";
export interface BackdropSkin {
    /** Fraction of each declared particle field actually drawn, per density. */
    detail: (density: Density) => number;
    /** Global alpha cap, per prominence and scheme. Light schemes stay fainter so
     *  a backdrop never competes with body text. */
    prominence: (p: Prominence, dark: boolean) => number;
    /** The opaque floor painted under every layer. The surface owns its own base
     *  rather than borrowing the app shell's, so a host can sit behind a shell that
     *  has gone transparent without the window showing through to nothing. */
    floor: (t: ColorTokens, dark: boolean) => string | null;
}
export declare const webSkin: BackdropSkin;
export declare const iosSkin: BackdropSkin;
export declare const androidSkin: BackdropSkin;
//# sourceMappingURL=backdrop.styles.d.ts.map