/**
 * Minimum viewport width (in pixels) to be considered a mobile device.
 * If the window width is smaller than this on initial load, the thumbnail side panel is hidden.
 */
export declare const MINIMUM_MOBILE_WIDTH: number;
/**
 * Direction flag for zoom-out operations.
 * Passed to {@link ZoomNav.calcNextZoom} to step down to the next lower zoom level.
 */
export declare const ZOOM_OUT: number;
/**
 * Direction flag for zoom-in operations.
 * Passed to {@link ZoomNav.calcNextZoom} to step up to the next higher zoom level.
 */
export declare const ZOOM_IN: number;
/**
 * Base scale factor applied when rendering PDF pages via pdf.js.
 * This value is multiplied by the user-selected zoom factor to determine the final rendering scale.
 */
export declare const BASIC_SCALE: number;
/**
 * Debounce delay (in milliseconds) between a window resize event and the actual page re-render.
 * Prevents excessive re-renders during continuous resizing.
 */
export declare const DELAY_RESIZE_MS: number;
/**
 * Maximum canvas area (in pixels) that the browser can reliably render.
 * If the canvas area exceeds this threshold, the output scale is reduced to 1x
 * to avoid blank or corrupted rendering on certain browsers.
 */
export declare const CANVAS_AREA_THRESHOLD: number;