// Zen-style film grain: a static 220px PNG tile of sparse BIPOLAR speckle (some pixels lighten,
// some darken, most near-transparent), so at full slider it reads as texture in the paint rather
// than gray haze on top. Opacity IS the grain slider, exactly like Zen's --zen-grainy-background-opacity.
export const GRAIN_URL = 'url("./grain-texture.png")';