// app.jsx — 應用外殼：登入分流 → 長者端 / 機構端
const { useState: useApp } = React;

function App() {
  const [mode, setMode] = useApp('login'); // login | elder | institution

  if (mode === 'elder') return <window.ElderApp onExit={() => setMode('login')} />;
  if (mode === 'institution') return <window.InstitutionApp onExit={() => setMode('login')} />;
  return <window.LoginScreen onElder={() => setMode('elder')} onInstitution={() => setMode('institution')} />;
}

ReactDOM.createRoot(document.getElementById('root')).render(<App />);