import { useState, useEffect } from 'react'; interface TopNavProps { onLogout?: () => void; } function Clock() { const [time, setTime] = useState(new Date()); useEffect(() => { const id = setInterval(() => setTime(new Date()), 1000); return () => clearInterval(id); }, []); return {time.toLocaleTimeString('zh-CN', { hour: '2-digit', minute: '2-digit' })}; } export function TopNav({ onLogout }: TopNavProps) { return ( ); }