/*
  cpt-city: jmn/jmn-c16 (cpt)

  A colourmap with monotonic luminance for simultaneous colour and
  grey-scale publications.

  J. McNames, "An effective color scale for simultaneous color and
  gray-scale publications," in IEEE Signal Processing Magazine,
  vol. 23, no. 1, pp. 82-96, Jan. 2006,

  author: James McNames
  copyright: Free to use
  year: 2009
  url: https://phillips.shef.ac.uk/pub/cpt-city/jmn
*/
linear-gradient(
  0deg,
  rgb(255, 255, 255)   0.000%,
  rgb(239, 222, 251)   6.667%,
  rgb(210, 198, 254)  13.333%,
  rgb(169, 188, 253)  20.000%,
  rgb(125, 194, 241)  26.667%,
  rgb( 85, 212, 212)  33.333%,
  rgb( 60, 234, 163)  40.000%,
  rgb( 57, 250,  99)  46.667%,
  rgb( 82, 233,  40)  53.333%,
  rgb(112, 183,   9)  60.000%,
  rgb(127, 127,   0)  66.667%,
  rgb(122,  75,   6)  73.333%,
  rgb(100,  35,  16)  80.000%,
  rgb( 67,  11,  23)  86.667%,
  rgb( 30,   1,  18)  93.333%,
  rgb(  0,   0,   0) 100.000%
);