Address PR #7 review comments: accessibility, performance, and code quality

[Copilot]

Implements fixes for 10 review comments on PR #7's UI polish changes, focusing on accessibility compliance, animation performance, and eliminating dead code.

Accessibility

• Added aria-label attributes to TopicChip buttons with descriptive text
• Implemented prefers-reduced-motion media query to respect user preferences for reduced animations

UX Corrections

• Fixed suggested topics to open YouTube search in new tab instead of setting invalid video URL:

// Before: setVideoUrl(`https://www.youtube.com/results?search_query=...`)
// After: window.open(searchUrl, '_blank', 'noopener,noreferrer')

• Added "Example Preview" badge to video preview card to clarify decorative intent
• Corrected navigation button group-hover by adding inline-flex items-center gap-1 classes

Performance & Maintainability

• Converted inline animationDelay styles to CSS custom properties (--animation-delay)
• Resolved shimmer animation keyframe conflict by renaming skeleton animation to skeleton-shimmer
• Added missing hover:bg-[position:100%_0] to danger/success button variants for consistent gradient shifts
• Removed 100+ lines of unused CSS utilities (.input-glow, .chip, .skeleton, .text-shadow-*)

Documentation

Noted branding inconsistency: homepage uses "Video2Learn" while dashboard/metadata retain "UVAI.io". Appears intentional for landing page marketing but flagged for verification if full rebrand intended.

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Review	Updated (UTC)
event-relay-web	Error		Jan 28, 2026 7:12pm
v0-uvai	Error		Jan 28, 2026 7:12pm