The HSL (hue, saturation, lightness) color space.
The Lab (CIELAB) color space. More closely matches human perception of lightness.
A newer color space, tending to be more accurate than Lab for this lightening and darkening, as seen in Section 13.1.6 in https://www.w3.org/TR/css-color-4/#lch-to-lab
This enumeration specifies possible values used for lightening and darkening.
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