/**
 * Applies a color theme to the document and persists it to `localStorage`.
 *
 * Sets the `data-theme` attribute on the document root element and stores
 * the selection so it can be restored on subsequent page loads via {@link restoreTheme}.
 *
 * @param theme - The theme to apply. Must be `"light"` or `"dark"`.
 * @throws Error if {@link theme} is not `"light"` or `"dark"`.
 */
declare const _default: (theme: string) => void;
export default _default;