Pastel
Colors with a lot of white in them: high lightness, low chroma. Baby blue, blush, mint. Soft, airy, and almost invisible on white.
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What it is
Pastels are high lightness plus low chroma: a hue with a lot of white mixed in. Technically they are tints. Baby blue, blush, mint, lavender, butter yellow. The word comes from the chalky pastel sticks, though the sticks themselves are not inherently pale: soft pastels use very little binder and come in fiercely saturated colors too. The pale ones are pale because white pigment was added, which is the same tinting move you make in a color picker.
They work when the job is gentle, approachable, or nostalgic: kids and parenting products, wellness, beauty, indie games, and anything borrowing from kawaii or 1950s Americana kitchen palettes. Pastels are also unusually good as large background fields, because several of them can coexist without fighting. That is why they show up in illustration systems where six category colors have to sit on one page.
Gotcha: pastels have almost no value contrast with white, so text on pastel, and pastel text on white, both fail accessibility fast. Treat pastels as surfaces and illustration fill, then bring a much darker version of the same hue (or a near-black) for type and icons. Second trap: pastel is not the same as muted. Pastel is light and soft, muted is dusty and mid-toned. Ask for pastel and you get nursery; ask for muted and you get Kinfolk.
Ask AI for it
Use a pastel palette: build every color at very high lightness (85 to 94 percent) with low chroma, so the hues read as soft tints (blush pink, powder blue, mint, lavender, butter yellow). Use pastels for backgrounds, cards, and illustration fills only. For all text, icons, and borders, use a much darker desaturated version of the same hue so body copy still clears 4.5:1 contrast. Keep the whole thing flat and soft with generous whitespace and rounded corners, no harsh black outlines.