Make light and sky cards glassy

[Cyber-preacher]

Summary

• Moves shared Surface backgrounds from flat color utilities into a reusable glass background layer.
• Lowers Light and Sky surface opacity and adds shared highlight/tint layers so cards read as translucent instead of white blocks.
• Converts Light-specific card hover/open states from opaque whites to translucent tints.

Validation

• yarn prettier --write src/components/Surface.tsx src/components/Surface.css src/components/GlassySection.css src/components/GlassyRecordCard.css src/styles/base.css
• yarn typecheck
• yarn build
• yarn test