feat: update UI components and enhance descriptions

[barbaraperic]

Description

• Added a new color to the UnoCSS configuration.
• Updated the AppLink component to center text for consistent mobile layout.
• Improved descriptions in KeyFeatures and Node Providers components for clarity and engagement.
• Adjusted button styles in PreFooter for better responsiveness.
• Added a ribbon to the Pricing component to highlight the best value.
• Enhanced Blog Card component styles for better visual appeal.
• Cleaned up formatting in the index and node-providers pages for consistency.

These changes aim to improve the user interface and experience across the application.

For reference, see Storacha Network Report.