/** Clear session cache (tests only). */
export declare function clearCssLengthPxCache(): void;
/**
 * Resolve a CSS length to pixels for layout math.
 * Numbers pass through; `var(--dimension-*)`, `calc(...)`, and `16px` resolve via a hidden probe.
 */
export declare function resolveCssLengthPx(value: number | string | undefined, fallback: number | string, context?: Element): number;