Added Complete Background Module for CSS Tutorial

[ajay-dhangar]

This PR adds the full content for the Background section of the CSS Tutorial. The goal is to provide clear explanations, practical examples, and beginner-friendly guidance for all major background-related CSS properties.

What’s Included

This update covers all files in the background module:

• background-color.mdx
• background-image.mdx
• background-gradient.mdx
• background-position.mdx
• background-size.mdx
• background-repeat.mdx
• background-attachment.mdx
• background-shorthand.mdx

Each file includes:

• Simple, clear explanations of the property
• Practical examples with code snippets
• Notes on common use-cases
• Best practices and visual guidance where helpful
• Consistent tone and structure as per the CSS tutorial guidelines

Purpose of This PR

This module is meant to help beginners understand how backgrounds work in CSS and how these properties interact with each other. The content progresses naturally from basic color backgrounds to more advanced concepts like gradients, positioning, and shorthand usage.

Additional Notes

• All examples follow modern CSS standards.
• Demo code blocks with Codepan live code preview.
• Formatting aligns with the rest of the tutorial structure.

Feedback Welcome

If you spot anything that can be improved—examples, explanations, or formatting—I’d love your suggestions.
This is part of the larger effort to build a complete, high-quality CSS learning path for CodeHarborHub.

[github-actions]

Thanks for adding the documentation label!


This pull request is now marked as needing content updates for the CodeHarborHub site. Please ensure the description contains all necessary technical details.

[github-actions]

Great job, @ajay-dhangar! 🎉 Thank you for submitting your pull request to CodeHarborHub. We appreciate your contribution and enthusiasm! Our team will review it soon. If you have any questions or need further assistance, feel free to reach out. Thanks for contributing!