Common fixes if red:
• Console > Firestore Database > Create database > Native mode > us-central (if step 4 = "database does not exist" or "Failed to get document" offline)
• Console > Firestore > Rules > paste Deploy/firestore.rules > Publish (if step 4 = permission-denied)
• Console > Authentication > Sign-in method > Email/Password > Enable (if login = operation-not-allowed)
• Console > Authentication > Settings > Authorized domains > Add + s-r-management.pages.dev (if login = unauthorized-domain)
• Run seed_admin.html first to create admin@S-R Management.com (if login = user-not-found)
• Check firebase-config.js matches Console > Project Settings > Your apps