for SU’s named colours, this is what you obtain see from ruby…
[[240, 248, 255, 255], "AliceBlue"]
[[250, 235, 215, 255], "AntiqueWhite"]
[[0, 255, 255, 255], "Cyan"]
[[127, 255, 212, 255], "Aquamarine"]
[[240, 255, 255, 255], "Azure"]
[[245, 245, 220, 255], "Beige"]
[[255, 228, 196, 255], "Bisque"]
[[0, 0, 0, 255], "Black"]
[[255, 235, 205, 255], "BlanchedAlmond"]
[[0, 0, 255, 255], "Blue"]
[[138, 43, 226, 255], "BlueViolet"]
[[165, 42, 42, 255], "Brown"]
[[222, 184, 135, 255], "BurlyWood"]
[[95, 158, 160, 255], "CadetBlue"]
[[127, 255, 0, 255], "Chartreuse"]
[[210, 105, 30, 255], "Chocolate"]
[[255, 127, 80, 255], "Coral"]
[[100, 149, 237, 255], "CornflowerBlue"]
[[255, 248, 220, 255], "Cornsilk"]
[[220, 20, 60, 255], "Crimson"]
[[0, 0, 139, 255], "DarkBlue"]
[[0, 139, 139, 255], "DarkCyan"]
[[184, 134, 11, 255], "DarkGoldenrod"]
[[169, 169, 169, 255], "DarkGray"]
[[0, 100, 0, 255], "DarkGreen"]
[[189, 183, 107, 255], "DarkKhaki"]
[[139, 0, 139, 255], "DarkMagenta"]
[[85, 107, 47, 255], "DarkOliveGreen"]
[[255, 140, 0, 255], "DarkOrange"]
[[153, 50, 204, 255], "DarkOrchid"]
[[139, 0, 0, 255], "DarkRed"]
[[233, 150, 122, 255], "DarkSalmon"]
[[143, 188, 143, 255], "DarkSeaGreen"]
[[72, 61, 139, 255], "DarkSlateBlue"]
[[47, 79, 79, 255], "DarkSlateGray"]
[[0, 206, 209, 255], "DarkTurquoise"]
[[148, 0, 211, 255], "DarkViolet"]
[[255, 20, 147, 255], "DeepPink"]
[[0, 191, 255, 255], "DeepSkyBlue"]
[[105, 105, 105, 255], "DimGray"]
[[30, 144, 255, 255], "DodgerBlue"]
[[178, 34, 34, 255], "FireBrick"]
[[255, 250, 240, 255], "FloralWhite"]
[[34, 139, 34, 255], "ForestGreen"]
[[255, 0, 255, 255], "Magenta"]
[[220, 220, 220, 255], "Gainsboro"]
[[248, 248, 255, 255], "GhostWhite"]
[[255, 215, 0, 255], "Gold"]
[[218, 165, 32, 255], "Goldenrod"]
[[128, 128, 128, 255], "Gray"]
[[0, 128, 0, 255], "Green"]
[[173, 255, 47, 255], "GreenYellow"]
[[240, 255, 240, 255], "Honeydew"]
[[255, 105, 180, 255], "HotPink"]
[[205, 92, 92, 255], "IndianRed"]
[[75, 0, 130, 255], "Indigo"]
[[255, 255, 240, 255], "Ivory"]
[[240, 230, 140, 255], "Khaki"]
[[230, 230, 250, 255], "Lavender"]
[[255, 240, 245, 255], "LavenderBlush"]
[[124, 252, 0, 255], "LawnGreen"]
[[255, 250, 205, 255], "LemonChiffon"]
[[173, 216, 230, 255], "LightBlue"]
[[240, 128, 128, 255], "LightCoral"]
[[224, 255, 255, 255], "LightCyan"]
[[250, 250, 210, 255], "LightGoldenrodYellow"]
[[144, 238, 144, 255], "LightGreen"]
[[211, 211, 211, 255], "LightGrey"]
[[255, 182, 193, 255], "LightPink"]
[[255, 160, 122, 255], "LightSalmon"]
[[32, 178, 170, 255], "LightSeaGreen"]
[[135, 206, 250, 255], "LightSkyBlue"]
[[119, 136, 153, 255], "LightSlateGray"]
[[176, 196, 222, 255], "LightSteelBlue"]
[[255, 255, 224, 255], "LightYellow"]
[[0, 255, 0, 255], "Lime"]
[[50, 205, 50, 255], "LimeGreen"]
[[250, 240, 230, 255], "Linen"]
[[128, 0, 0, 255], "Maroon"]
[[102, 205, 170, 255], "MediumAquamarine"]
[[0, 0, 205, 255], "MediumBlue"]
[[186, 85, 211, 255], "MediumOrchid"]
[[147, 112, 219, 255], "MediumPurple"]
[[60, 179, 113, 255], "MediumSeaGreen"]
[[123, 104, 238, 255], "MediumSlateBlue"]
[[0, 250, 154, 255], "MediumSpringGreen"]
[[72, 209, 204, 255], "MediumTurquoise"]
[[199, 21, 133, 255], "MediumVioletRed"]
[[25, 25, 112, 255], "MidnightBlue"]
[[245, 255, 250, 255], "MintCream"]
[[255, 228, 225, 255], "MistyRose"]
[[255, 228, 181, 255], "Moccasin"]
[[255, 222, 173, 255], "NavajoWhite"]
[[0, 0, 128, 255], "Navy"]
[[253, 245, 230, 255], "OldLace"]
[[128, 128, 0, 255], "Olive"]
[[107, 142, 35, 255], "OliveDrab"]
[[255, 165, 0, 255], "Orange"]
[[255, 69, 0, 255], "OrangeRed"]
[[218, 112, 214, 255], "Orchid"]
[[238, 232, 170, 255], "PaleGoldenrod"]
[[152, 251, 152, 255], "PaleGreen"]
[[175, 238, 238, 255], "PaleTurquoise"]
[[219, 112, 147, 255], "PaleVioletRed"]
[[255, 239, 213, 255], "PapayaWhip"]
[[255, 218, 185, 255], "PeachPuff"]
[[205, 133, 63, 255], "Peru"]
[[255, 192, 203, 255], "Pink"]
[[221, 160, 221, 255], "Plum"]
[[176, 224, 230, 255], "PowderBlue"]
[[128, 0, 128, 255], "Purple"]
[[255, 0, 0, 255], "Red"]
[[188, 143, 143, 255], "RosyBrown"]
[[65, 105, 225, 255], "RoyalBlue"]
[[139, 69, 19, 255], "SaddleBrown"]
[[250, 128, 114, 255], "Salmon"]
[[244, 164, 96, 255], "SandyBrown"]
[[46, 139, 87, 255], "SeaGreen"]
[[255, 245, 238, 255], "Seashell"]
[[160, 82, 45, 255], "Sienna"]
[[192, 192, 192, 255], "Silver"]
[[135, 206, 235, 255], "SkyBlue"]
[[106, 90, 205, 255], "SlateBlue"]
[[112, 128, 144, 255], "SlateGray"]
[[255, 250, 250, 255], "Snow"]
[[0, 255, 127, 255], "SpringGreen"]
[[70, 130, 180, 255], "SteelBlue"]
[[210, 180, 140, 255], "Tan"]
[[0, 128, 128, 255], "Teal"]
[[216, 191, 216, 255], "Thistle"]
[[255, 99, 71, 255], "Tomato"]
[[64, 224, 208, 255], "Turquoise"]
[[238, 130, 238, 255], "Violet"]
[[245, 222, 179, 255], "Wheat"]
[[255, 255, 255, 255], "White"]
[[245, 245, 245, 255], "WhiteSmoke"]
[[255, 255, 0, 255], "Yellow"]
[[154, 205, 50, 255], "YellowGreen"]
you can also interrogate the UX colours used as well…
john