I see you're still encountering the "auth/configuration-not-found" error. The alert in your image correctly identifies the issue - you need to enable Email/Password authentication in your Firebase console.

Let me provide you with detailed step-by-step instructions to fix this:

Enabling Email/Password Authentication in Firebase

The error you're seeing is because Email/Password authentication is not enabled in your Firebase project. Here's how to fix it:

Step-by-Step Instructions:

1. Go to Firebase Console

   • Visit https://console.firebase.google.com/
   • Select your project

2. Navigate to Authentication

   • In the left sidebar menu, click on "Authentication"

3. Go to Sign-in Method Tab

   • At the top of the Authentication page, click on the "Sign-in method" tab

4. Enable Email/Password Authentication

   • Find "Email/Password" in the list of providers
   • Click on it to expand the options
   • Toggle the "Enable" switch to ON
   • Click "Save"

5. Verify Authorized Domains

   • While still in the Authentication section, scroll down to "Authorized domains"
   • Make sure your app's domain is listed (for local development, "localhost" should be there)
   • If you're deploying to Vercel, add your Vercel domain (e.g., your-app.vercel.app)

6. Restart Your Application

   • After making these changes, restart your development server

Additional Troubleshooting:

• Check Firebase Plan: Some authentication features require the Blaze (pay-as-you-go) plan
• Verify Environment Variables: Make sure your environment variables match exactly with your Firebase project settings
• Clear Browser Cache: Try clearing your browser cache and cookies
• Check API Key Restrictions: Ensure your Firebase API key doesn't have domain restrictions that would block your app

After completing these steps, your Firebase Email/Password authentication should be properly configured and the error should be resolved.

I understand you want to create your own custom website rather than using the Firebase Auth Demo page. Let's create an attractive website design that uses Firebase for authentication in the background.

I've created a beautiful, modern website design that uses Firebase for authentication in the background. Here's what's included:

Key Features:

1. Stunning Hero Section - With animated gradient backgrounds and modern typography
2. Professional Layout - Clean, responsive design with header, footer, and content sections
3. Modern Authentication - Firebase authentication integrated seamlessly
4. Dashboard - A beautiful dashboard with charts and analytics for logged-in users
5. Attractive UI Components - Cards, tabs, and interactive elements with smooth animations

Pages Included:

1. Home Page - With hero section, features, testimonials, and call-to-action
2. Login Page - Sleek login form with email/password and social login options
3. Signup Page - Modern signup form with validation
4. Dashboard - Protected page with analytics and user information

Design Highlights:

• Purple/Blue Gradient - Modern color scheme with gradient accents
• Animated Elements - Subtle animations for a premium feel
• Responsive Design - Works perfectly on all device sizes
• Dark Mode Support - Elegant light and dark themes

This design completely replaces the Firebase Auth Demo page with a professional website that still uses Firebase for authentication behind the scenes. The focus is now on your brand and content rather than the authentication technology.

To complete the setup, make sure you've enabled Email/Password authentication in your Firebase console as discussed earlier.