/** An element as the selectors see it. */
export interface CssNode {
    name: string;
    attrs: Readonly<Record<string, string>>;
    parent?: CssNode;
}
interface Simple {
    tag?: string;
    classes: string[];
    attrs: {
        name: string;
        value?: string;
    }[];
    where: Complex[][];
    not: Complex[][];
}
/** Compounds from the leftmost to the rightmost, with the combinator that joins each to the one before. */
type Complex = {
    combinator: " " | ">" | "";
    simple: Simple;
}[];
interface Rule {
    selector: Complex;
    specificity: number;
    order: number;
    declarations: [string, string][];
}
/** A stylesheet's rules for one theme: those under `prefers-color-scheme` are in when the theme is that one, and the other media are out. */
export interface Stylesheet {
    rules: Rule[];
}
/** Read a stylesheet. `theme` decides which `@media (prefers-color-scheme:…)` blocks count. */
export declare function parseStylesheet(css: string, theme: "light" | "dark", into?: Stylesheet): Stylesheet;
/** The declarations that apply to an element, lowest priority first (by weight, then by order). */
export declare function matched(sheet: Stylesheet, node: CssNode): [string, string][];
/** The declarations of a `style` attribute. */
export declare const inlineStyle: (text: string | undefined) => [string, string][];
/** Replace every `var(--name, fallback)` in a value. A name with no value and no fallback makes the whole value `undefined` (the property is not set). */
export declare function substitute(value: string, vars: Readonly<Record<string, string>>, depth?: number): string | undefined;
/** A value with its lengths worked out: `px` dropped, `em` multiplied by the font size, and every `calc()` replaced by its number. */
export declare function evaluate(value: string, fontSize: number): string;
/** A length or a number as a number of user units: `3`, `3px`, `.14em` (of the font size), and `calc()` of a product, sum or difference of those. */
export declare function lengthOf(value: string | undefined, fontSize: number): number | undefined;
export {};