fix: make login and signup buttons visible in mobile menu (#249, #266)

[udaykiran243]

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Thanks!

📌 Description

This PR fixes a bug where the "Login" and "Get Started" buttons were hidden in the mobile view menu.

What problem does it solve?

• In mobile view, the authentication buttons were inadvertently hidden by a CSS selection rule intended for the desktop header layout.
• Use of .mobile-auth container now correctly displays these buttons as block elements in the slide-out menu.

🔗 Related Issue

Fixes #249

Closes #266
Closes #231

🛠 Type of Change

• 🐛 Bug fix (non-breaking change fixing an issue)

✅ Checklist

• Code follows project coding standards
• Self-review completed
• Tested on valid mobile resolutions

[vercel]

@udaykiran243 is attempting to deploy a commit to the Karan Manickam's projects Team on Vercel.

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[github-actions]

🎉 Thanks for the PR, @udaykiran243!

We really appreciate you taking the time to contribute to CryptoHub! 💙

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✅ PR Checklist

Before we review, please ensure:

• Your code follows the project's coding standards
• All file changes are accurate and intentional
• You've tested your changes locally
• Any review comments have been addressed

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We'll review your PR as soon as possible. Keep up the great work! ✨