- Left: ⬢ PURO AI brand + '5→1' headline + three-line value props
- Right: existing form (OAuth, Turnstile, 2FA all preserved unchanged)
- Heading changed from t('auth.welcomeBack') to '登录' — i18n key consolidation in Task 11
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>