interface SchedulingTimezoneOption {
    tz: string;
    label: string;
}
interface SchedulingTimezoneGroup {
    region: string;
    values: SchedulingTimezoneOption[];
}
declare const DEFAULT_TIMEZONE_GROUPS: SchedulingTimezoneGroup[];
/**
 * Membership lookup. Useful for rendering a dropdown vs. switching to the
 * "Custom…" text input when the current value isn't in the curated set.
 */
declare function isInTimezoneGroups(tz: string, groups: SchedulingTimezoneGroup[]): boolean;
/**
 * Detect the browser's IANA timezone name. Returns null in non-browser
 * environments (SSR, tests) or when the platform doesn't expose
 * Intl.DateTimeFormat().resolvedOptions().
 */
declare function detectBrowserTimezone(): string | null;

export { DEFAULT_TIMEZONE_GROUPS, type SchedulingTimezoneGroup, type SchedulingTimezoneOption, detectBrowserTimezone, isInTimezoneGroups };