/**
 * Styles table integrity.
 *
 * Every xf in `cellXfs` references indices into `numFmts`, `fonts`,
 * `fills`, `borders`. Out-of-bounds references produce style corruption
 * on load (Excel falls back to the default style silently, so this is a
 * warning-severity check — it's a strong signal of a broken writer but
 * not a hard "Excel cannot open" issue).
 *
 * `numFmts` uses numeric IDs, including ~100 built-in IDs < 164 that are
 * never declared. We only flag ids >= 164 that have no matching numFmt
 * entry.
 */
import type { ValidationContext } from "./context.js";
export declare function checkStyles(ctx: ValidationContext): void;