Metro Visual System · Color
Every line hue is drawn as concentric rings stepping from the flat shade to the applied value. Pick a ground and a shade: every hue reports what that shade actually measures against that ground.
The steps do not hold hue. Orange runs 14° → 22° →
35°, blue runs 204° → 199° → 192°,
green 152° → 157° → 164°. Saturation climbs alongside.
The system's own rule is that hue is identity and only lightness moves between the core and
the applied value — these tints warm as they lift instead. Either the rule needs amending to
describe what the palette does, or the palette needs re-deriving from its cores.
This is a dark-ground palette. On #1A1A1A every step of every hue clears
AA except graphite's core. On #F2F2F2 only graphite's core clears it — every
other core fails, and the lighter the step the worse it gets. A line hue that has to survive a
light platform sign is not in this set yet.
Six families are drawn here, read from the labels in the source artwork. The reference is
cropped mid-word, so two of the eight are missing — likely the violet and one other,
given the contrast plate already on the page carries #793989 and
#AD66BF. Send those and they drop straight into the array.