Variations of how colour moves across the five spiral cells (Study tools → Science → Tip → AI → Delight, big → small, winding into the eye). Shipped v1 mixes the palette accent into the card base at 3 → 26 % — this is open decision #3 in design-welcome-screen.md. Every variant is defined against the palette variables, so it tracks Default/Edo × light/dark automatically. Click a thumbnail to load it into the big preview; the swatch row gives the resolved per-cell colours for the Swift handoff. Reverse flips whichever gradient is showing — colour on the stage, quiet eye — and applies to every thumbnail too. Glow lays a radial accent wash on the pane behind the spiral, anchored at the eye (at the stage when reversed); Glass makes every cell slightly translucent so it picks the wash up. Opens on the current pick: Whisper · reversed, glow 11 %, glass 28 %. Hue-walk variants use OKLCH relative colours — current Safari/Chrome only.
Porting note. Group A is a one-line Swift change — the five tint: values in WelcomeHomeView.swift (an accent.opacity(t) overlay is exactly color-mix(in srgb, accent t%, card)). Groups B and C need real per-cell colours (or a hue-rotation helper) per palette × appearance — lift them from the swatch row in all four combinations. The Glow + Glass layer maps to a RadialGradient behind the spiral plus alpha on the cell fills — both cheap in SwiftUI; the swatch row shows the cell alpha when Glass is on.