This color style is derived from the R Colorspace package, which uses the perceptually uniform HCL (Hue–Chroma–Luminance) color model to ensure balanced and visually consistent maps. Based on work by Zeileis, A., Hornik, K., & Murrell, P. (2009). Escaping RGBland: Selecting colors for statistical graphics. Computational Statistics & Data Analysis, 53(9), 3259–3270.