/**
 * Build a list of focusable elements inside a container (same selector used by
 * Lit and React fileupload preview modals). Hidden elements are filtered out.
 */
export declare function getFocusableElements(container: HTMLElement | null | undefined): HTMLElement[];
/**
 * Keyboard handler that wraps Tab / Shift-Tab focus around the first and last
 * focusable elements inside a container. Returns `true` if the event was handled.
 *
 * Call from a `keydown` listener on the modal root.
 */
export declare function trapTabInside(event: KeyboardEvent, container: HTMLElement | null | undefined): boolean;