// App — compose the full marketing page function detectInitialLang() { try { const saved = localStorage.getItem('jk-lang'); if (saved === 'de' || saved === 'pl') return saved; } catch (e) {} const prefs = (navigator.languages && navigator.languages.length) ? navigator.languages : [navigator.language || 'de']; for (const p of prefs) { const code = (p || '').toLowerCase().slice(0, 2); if (code === 'pl') return 'pl'; if (code === 'de') return 'de'; } return 'de'; } function App() { const [lang, _setLang] = React.useState(detectInitialLang); const setLang = (v) => { _setLang(v); try { localStorage.setItem('jk-lang', v); } catch (e) {} }; React.useEffect(() => { document.documentElement.lang = lang; }, [lang]); return ( <>