E02.1 · CATEGORICAL
Distinct, limited.
For unordered categories, use a small set of distinct hues drawn from the brand — ink, stone, vermilion, then functional colours. Cap at six; beyond that, group the tail.
SETInk · stone · vermilion
MAX6 categories
TAILGroup as "other"
ORDERStable across charts
E02.2 · SEQUENTIAL
One hue, light to dark.
For ordered magnitude, use a single-hue ramp — pale vermilion to deep. Lightness encodes value; never a rainbow, which invents categories that aren't there.
RAMPVermilion 100→700
ENCODELightness = value
STEPS5–7
AVOIDRainbow scales
E02.3 · SEMANTIC
Green up, red down.
Performance data uses the functional set — success green, error red, warning amber. These are reserved meanings; never use semantic colours for ordinary categories.
UPSuccess green
DOWNError red
WARNAmber
RESERVEDMeaning only
E02.4 · ACCESSIBILITY
Never colour alone.
Around 8% of men can't separate red and green, so colour is always paired with a label, shape or direct value. Palettes are checked against colour-blind simulation.
PAIRColour + label
CHECKCVD simulation
DELTAArrow + colour
CONTRASTOn both grounds