Feat: Add glass navbar component

[codedbydollys10]

Pull Request Description

Adds a reusable glass navbar component to EaseMotion CSS with a built-in backdrop blur effect, sticky positioning support, and a stronger blur variant. The update includes a demo section in demo.html and documentation in README.md.

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Type of Change

• 🧩 New component

Closes #1272

Submission Checklist

⚠️ PRs that fail this checklist will be closed without review.

• All changes are inside submissions/examples/your-feature-name/
• Includes demo.html — self-contained, opens in browser with no server
• Includes style.css — raw CSS for the proposed feature
• Includes README.md — what it does, how to use it, why it fits EaseMotion CSS
• No changes to core
• No changes to components
• One feature per PR (no bundled unrelated changes)

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Feature Description

What does this add?

Introduces a new ease-navbar-glass component with glassmorphism styling, plus ease-navbar-glass-sticky and ease-navbar-glass-blur modifiers for sticky and enhanced blur variants.

How does a developer use it?

<nav class="ease-navbar-glass" aria-label="Primary navigation">
  <div class="ease-navbar-brand">EaseMotion</div>
  <div class="ease-navbar-menu">
    <a class="ease-navbar-item" href="#">Home</a>
    <a class="ease-navbar-item" href="#">Features</a>
    <a class="ease-navbar-item" href="#">Contact</a>
  </div>
</nav>

Why does it fit EaseMotion CSS?

This aligns with EaseMotion CSS’s human-readable naming and CSS-only component approach. It builds on the existing glassmorphism card pattern while providing a reusable navigation container with responsive layout, accessibility-friendly focus styling, and graceful fallback for browsers without backdrop-filter.

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Demo

• Demo added (demo.html shows the navbar examples and opens directly in a browser)

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Browser Testing

• Chrome
• Firefox
• Edge
• Safari (optional but appreciated)

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Notes for Maintainer

• The new component is implemented in navbar.css.
• easemotion.css now imports the new navbar component.
• README.md includes usage examples for all three classes.
• easemotion.min.css was regenerated with the updated build script.

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[github-actions]

📊 CSS Bundle Size Benchmark

This PR changes the size of easemotion.min.css.

Metric	Base Branch	This PR	Difference
Raw	39.16 KB	41.06 KB	📈 +1.89 KB
Gzip	7.16 KB	7.46 KB	📈 +0.30 KB
Brotli	6.19 KB	6.46 KB	📈 +0.27 KB

[codedbydollys10]

hey @SAPTARSHI-coder pls review my pr nd merge it