Avoid Gradient Banding

SHOULD: Build soft glows with `radial-gradient()` rather than a filled rectangle scaled and run through `filter: blur()` — the blur+scale route bands. Where a gradient still bands, fade it with a `mask-image` gradient instead of stacking more blur.

Scaling and blurring filled rectangles causes banding — use radial gradients instead

.glow { background: radial-gradient(circle, oklch(0.7 0.2 250 / 0.5), transparent 70%); }