A list of built-in CSS colors

css_colors.tinkerwell.php

$page = Http::get('https://www.w3schools.com/cssref/css_colors.asp')->body();
$html = new Symfony\Component\DomCrawler\Crawler($page);

$names = [];

foreach($html->filter('#colornamestable .colornamespan') as $element) {
  $names[] = strtolower($element->firstChild->firstChild->wholeText);
}

$values = [];

foreach($html->filter('#colornamestable .colorhexspan') as $color) {
 	$values[] = $color->firstChild->firstChild->wholeText; 
}

$colors = array_combine($names, $values);

json_encode($colors);

css_colors_list.json

{
   "aliceblue":"#F0F8FF",
   "antiquewhite":"#FAEBD7",
   "aqua":"#00FFFF",
   "aquamarine":"#7FFFD4",
   "azure":"#F0FFFF",
   "beige":"#F5F5DC",
   "bisque":"#FFE4C4",
   "black":"#000000",
   "blanchedalmond":"#FFEBCD",
   "blue":"#0000FF",
   "blueviolet":"#8A2BE2",
   "brown":"#A52A2A",
   "burlywood":"#DEB887",
   "cadetblue":"#5F9EA0",
   "chartreuse":"#7FFF00",
   "chocolate":"#D2691E",
   "coral":"#FF7F50",
   "cornflowerblue":"#6495ED",
   "cornsilk":"#FFF8DC",
   "crimson":"#DC143C",
   "cyan":"#00FFFF",
   "darkblue":"#00008B",
   "darkcyan":"#008B8B",
   "darkgoldenrod":"#B8860B",
   "darkgray":"#A9A9A9",
   "darkgrey":"#A9A9A9",
   "darkgreen":"#006400",
   "darkkhaki":"#BDB76B",
   "darkmagenta":"#8B008B",
   "darkolivegreen":"#556B2F",
   "darkorange":"#FF8C00",
   "darkorchid":"#9932CC",
   "darkred":"#8B0000",
   "darksalmon":"#E9967A",
   "darkseagreen":"#8FBC8F",
   "darkslateblue":"#483D8B",
   "darkslategray":"#2F4F4F",
   "darkslategrey":"#2F4F4F",
   "darkturquoise":"#00CED1",
   "darkviolet":"#9400D3",
   "deeppink":"#FF1493",
   "deepskyblue":"#00BFFF",
   "dimgray":"#696969",
   "dimgrey":"#696969",
   "dodgerblue":"#1E90FF",
   "firebrick":"#B22222",
   "floralwhite":"#FFFAF0",
   "forestgreen":"#228B22",
   "fuchsia":"#FF00FF",
   "gainsboro":"#DCDCDC",
   "ghostwhite":"#F8F8FF",
   "gold":"#FFD700",
   "goldenrod":"#DAA520",
   "gray":"#808080",
   "grey":"#808080",
   "green":"#008000",
   "greenyellow":"#ADFF2F",
   "honeydew":"#F0FFF0",
   "hotpink":"#FF69B4",
   "indianred ":"#CD5C5C",
   "indigo  ":"#4B0082",
   "ivory":"#FFFFF0",
   "khaki":"#F0E68C",
   "lavender":"#E6E6FA",
   "lavenderblush":"#FFF0F5",
   "lawngreen":"#7CFC00",
   "lemonchiffon":"#FFFACD",
   "lightblue":"#ADD8E6",
   "lightcoral":"#F08080",
   "lightcyan":"#E0FFFF",
   "lightgoldenrodyellow":"#FAFAD2",
   "lightgray":"#D3D3D3",
   "lightgrey":"#D3D3D3",
   "lightgreen":"#90EE90",
   "lightpink":"#FFB6C1",
   "lightsalmon":"#FFA07A",
   "lightseagreen":"#20B2AA",
   "lightskyblue":"#87CEFA",
   "lightslategray":"#778899",
   "lightslategrey":"#778899",
   "lightsteelblue":"#B0C4DE",
   "lightyellow":"#FFFFE0",
   "lime":"#00FF00",
   "limegreen":"#32CD32",
   "linen":"#FAF0E6",
   "magenta":"#FF00FF",
   "maroon":"#800000",
   "mediumaquamarine":"#66CDAA",
   "mediumblue":"#0000CD",
   "mediumorchid":"#BA55D3",
   "mediumpurple":"#9370DB",
   "mediumseagreen":"#3CB371",
   "mediumslateblue":"#7B68EE",
   "mediumspringgreen":"#00FA9A",
   "mediumturquoise":"#48D1CC",
   "mediumvioletred":"#C71585",
   "midnightblue":"#191970",
   "mintcream":"#F5FFFA",
   "mistyrose":"#FFE4E1",
   "moccasin":"#FFE4B5",
   "navajowhite":"#FFDEAD",
   "navy":"#000080",
   "oldlace":"#FDF5E6",
   "olive":"#808000",
   "olivedrab":"#6B8E23",
   "orange":"#FFA500",
   "orangered":"#FF4500",
   "orchid":"#DA70D6",
   "palegoldenrod":"#EEE8AA",
   "palegreen":"#98FB98",
   "paleturquoise":"#AFEEEE",
   "palevioletred":"#DB7093",
   "papayawhip":"#FFEFD5",
   "peachpuff":"#FFDAB9",
   "peru":"#CD853F",
   "pink":"#FFC0CB",
   "plum":"#DDA0DD",
   "powderblue":"#B0E0E6",
   "purple":"#800080",
   "rebeccapurple":"#663399",
   "red":"#FF0000",
   "rosybrown":"#BC8F8F",
   "royalblue":"#4169E1",
   "saddlebrown":"#8B4513",
   "salmon":"#FA8072",
   "sandybrown":"#F4A460",
   "seagreen":"#2E8B57",
   "seashell":"#FFF5EE",
   "sienna":"#A0522D",
   "silver":"#C0C0C0",
   "skyblue":"#87CEEB",
   "slateblue":"#6A5ACD",
   "slategray":"#708090",
   "slategrey":"#708090",
   "snow":"#FFFAFA",
   "springgreen":"#00FF7F",
   "steelblue":"#4682B4",
   "tan":"#D2B48C",
   "teal":"#008080",
   "thistle":"#D8BFD8",
   "tomato":"#FF6347",
   "turquoise":"#40E0D0",
   "violet":"#EE82EE",
   "wheat":"#F5DEB3",
   "white":"#FFFFFF",
   "whitesmoke":"#F5F5F5",
   "yellow":"#FFFF00",
   "yellowgreen":"#9ACD32"
}