The palette based on Flat UI.
palette_flat(palette = "contrast", reverse = FALSE, ...)Character name of palette. Depending on the color scale, can
be "full", "ice", "rainbow", "complement",
"contrast" or "light" (for dark themes).
Boolean indicating whether the palette should be reversed.
Additional arguments to pass to colorRampPalette().
This function is usually not called directly, but from within
scale_color_flat().