UI revamp

[kshitijk4poor]

🎨 UI revamp

🚀 Changes

• 🖌️ Integrated the Zephyr theme from Bootswatch (bootswatch.com/zephyr/)
• 🔧 Fixed navbar issues, now it correctly shows the current active states for the navbar items
• ☀️ Supports both Light and Dark themes

🌟 Benefits

• 💅 Fresh, modern look with the "breezy and beautiful" Zephyr theme
• 📱 Enhanced user experience with responsive navbar
• 🎭 Improved overall UI consistency across the application

🧪 Testing

• Verified theme application across all pages
• Tested navbar functionality on various screen sizes
• Ensured no conflicts with existing custom styles

☑️ TODO

• [x] Implement theme toggling
• [ ] add dark mode for queue.jinja2
• [ ] Add video demo