Enhance Color Changer App with VIBGYOR Logic and Semantic Styling

[AnupmaMishra12]

### 🔧 What I Did:

• Added a semantic <h1> heading to guide users
• Implemented VIBGYOR color logic using JavaScript
• Made background and heading color change dynamically
• Ensured contrast-aware text visibility for accessibility
• Used semantic HTML structure with <main> and <section>
• Styled buttons with hover effects and transitions for better UX

🌈 Why This Matters:

This update makes the Color Changer App more interactive, educational, and visually engaging — inspired by the physics concept of VIBGYOR. It also improves accessibility and code readability.

🙌 Thank You:

Thanks for maintaining this beginner-friendly repo! I'm excited to contribute again and learn more through open source.

Enhanced by Anupma Mishra: Added VIBGYOR color logic and improved accessibility using semantic HTML.

[AnupmaMishra12]

Hi @sahbanhaxar 👋
I’ve added VIBGYOR-based color logic and improved the UI with semantic HTML and contrast-aware styling. The heading now changes color dynamically with the background, ensuring better accessibility and visual impact. Hope this adds value to the project — looking forward to your feedback!