Ground & Colour
The base, the accent and the argument between them. Every turn of that cycle was justified as a matter of taste and paid for as a matter of rendering cost.
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Off-white is a decision
Almost nothing ships on pure white any more, and the warm off-white that replaced it has become its own monoculture — a default wearing the costume of a choice.
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Two colours far enough apart
A palette needs internal difference to be a palette. Two accents thirty degrees apart in hue read as one colour and a mistake.
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The accent that is only a rule
A colour used exclusively on 2px borders is not in the palette. It has to hold area.
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Gradients read as depth
Until they are printed, or seen on a panel that bands them.