d3.lab(l, a, b[, opacity]) d3.lab(specifier) d3.lab(color)
Constructs a new Lab color. The channel values are exposed as l, a and b properties on the returned instance. Use the Lab color picker to explore this color space.
If l, a and b are specified, these represent the channel values of the returned color; an opacity may also be specified. If a CSS Color Module Level 3 specifier string is specified, it is parsed and then converted to the Lab color space. See color for examples. If a color