type OnChange = (value: string) => void;
export declare const IS_SERVER: boolean;
/**
 * Frequency of retries for CSS variable lookup in milliseconds
 */
export declare const LOOKUP_FREQUENCY = 5000;
/**
 * Maximum number of retries for a CSS variable lookup
 */
export declare const LOOKUP_MAX_RETRIES = 5;
export declare const convertRemToPixels: (rem: number) => number;
/**
 * Parse CSS variable declared on root to number
 *
 * @precondition CSS variable must be declared on root
 *
 * @param cssVar - CSS variable string to parse
 *
 * @returns string - value of the CSS variable. If not found, returns empty string
 *
 */
export declare const getCSSVar: (cssVar: string) => string;
/**
 * Parse size string to number
 *
 * @param size - size string to parse
 *
 * @precondition size must be in rem or px
 *
 * @returns number - parsed value of the size in px
 *
 */
export declare const parseSizeString: (size: string) => number;
/**
 * CSSLookup is a singleton class that provides a way to lookup CSS variables
 *
 * Recommended not to use this class with variables that depend on light/dark theme
 * as this class returns memoized values
 */
declare class CSSLookup {
    #private;
    lookupMap: Map<string, string>;
    subscribers: Map<string, OnChange[]>;
    private static instance;
    private constructor();
    /**
     * Returns the singleton instance of the CSSLookup class.
     * If the instance does not exist, it creates one.
     */
    static getInstance(): CSSLookup;
    /**
     * Find CSS variable value. Takes in a CSS variable string of format var(--varName)
     * or --varName. If the value is not found, it will retry the lookup every second
     * and will call the onChange function with the value once it is found.
     *
     * @param cssVar
     * @param onChange - callback to call when value is found. if not specified, will
     * not retry lookup
     */
    findVar(cssVar: string, onChange?: OnChange): string | undefined;
    /**
     * Find CSS variable value. Retries if not found initially.
     *
     * Lookup max retries and interval specified by LOOKUP_MAX_RETRIES and LOOKUP_FREQUENCY
     *
     * If callback is not specified, retries will not be attempted. This is useful for
     * cursory lookups where the value is not critical (like initial value of useState
     * hook)
     *
     * @param cssVar CSS variable to find
     * @param onChange callback to call when value is found
     * @param prevRetries previous number of retries
     */
    findVarHelper(cssVar: string, prevRetries: number, onChange?: OnChange): string;
    /**
     * Unsubscribe from CSS variable value
     *
     * @param cssVar
     * @param onChange
     */
    unsubscribe(cssVar: string, onChange: OnChange): void;
}
export declare const CSSManager: Readonly<CSSLookup>;
export {};