
## Effect Resources

### In this system

- [Effects overview](/foundations/effects/) — shadow samples
- [Effect guidelines](/foundations/effects-guidelines/) — usage rules
- Token source: `src/handoff/nextgen/tokens/tailwind.css` — `black-alpha-*`, `white-alpha-*`, `bg-bg-hover`

### Web references

- [CSS `linear-gradient` (MDN)](https://developer.mozilla.org/en-US/docs/Web/CSS/gradient/linear-gradient) — basis for Tailwind `bg-linear-to-*` overlays
- [CSS `box-shadow` (MDN)](https://developer.mozilla.org/en-US/docs/Web/CSS/box-shadow) — when a component already documents a shadow
- [Under-engineered shadows (Adrian Roselli)](https://adrianroselli.com/2019/06/under-engineered-shadows.html) — accessibility notes on elevation

Prefer **surface + overlay tokens** over a global elevation scale. Match an existing block (e.g. `full_cta`, `pre_footer`) when you need atmosphere behind type.
