import type { Page } from '@playwright/test';
/**
 * Parse the px width BOUNDARIES a single `@media` condition introduces — the widths
 * at which its match flips. A `min-width: V` opens a band at `V`; a `max-width: V`
 * keeps the band below active through `V`, so the next band opens at `V + 1`. Range
 * syntax (`width >= V`, `V <= width`, `width < V`, …) is normalised the same way.
 * `em`/`rem` are resolved against `rootFontPx`. Non-width conditions yield nothing.
 */
export declare function mediaTextWidthBoundaries(mediaText: string, rootFontPx?: number): number[];
/**
 * Turn breakpoint boundaries into one representative viewport width per band: the
 * base band below the first boundary uses `baseWidth` (clamped strictly inside it),
 * every other band its lower boundary. With no boundaries (no width `@media` rules)
 * the layout is band-invariant, so a single `noQueryWidth` covers it. Ascending,
 * de-duplicated.
 */
export declare function widthsFromBoundaries(boundaries: number[], opts?: {
    baseWidth?: number;
    noQueryWidth?: number;
}): number[];
/**
 * Detect the viewport widths to sweep for the currently-loaded page: read every
 * `@media` width breakpoint from the live CSSOM and return one width per band.
 * Throws if any stylesheet is unreadable (cross-origin) — detection is authoritative
 * or it fails; it never guesses. Call after the page has loaded its styles.
 */
export declare function detectViewportWidths(page: Page, opts?: {
    baseWidth?: number;
    noQueryWidth?: number;
}): Promise<number[]>;