How to detect neutral temperature
Any gray with saturation greater than 0% has a temperature. Convert the gray hex to HSL: if hue is 0-70°, it leans warm (red/amber undertone); if hue is 180-270°, it leans cool (blue/green undertone); if saturation is effectively 0, it is true neutral. Most design systems choose a subtle temperature — 3-8% saturation — that is invisible in isolation but creates clear warmth or coolness when used as a large background surface. The Editorial Warmth collection demonstrates warm neutrals at work: amber-silk, apricot-whisper, and honey variants at low saturation produce surfaces that feel materially warm without being overtly colored.
