Use precalculated RGB colors for performance

src/darkmode.ts

@@ -1,3 +1,163 @@
+/* https://developer.mozilla.org/en-US/docs/Web/CSS/color_value
+  $$('#colors_table tbody tr')
+    .map((row) => {
+      const [name, hex] = Array.from(row.children).slice(-3);
+      return [name.innerText.trim().replace(/\s.+/g, ''), hex.innerText.trim()];
+    }).sort((a, b) => [a[0], b[0]].sort()[0] === a[0] ? -1 : 1)
+    .map(([name, hex]) => `${name} : '${hex}',`)
+    .join('\n')
+*/
+const namedColors = {
+  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",
+  darkgreen: "#006400",
+  darkgrey: "#a9a9a9",
+  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",
+  green: "#008000",
+  greenyellow: "#adff2f",
+  grey: "#808080",
+  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",
+  lightgreen: "#90ee90",
+  lightgrey: "#d3d3d3",
+  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",
+};
+
 interface ColorRGB {
   r: number;
   g: number;
@@ -73,6 +233,10 @@ function rgbToHsv({ r, g, b }: ColorRGB): ColorHSV {
 
 // Hacky way to get RGB values FOR SURE!
 function nameToRGB(name: string): ColorRGB {
+  if (namedColors[name]) {
+    return parseColor(namedColors[name]);
+  }
+
   // Create fake div
   const fakeDiv = document.createElement("div");
   fakeDiv.style.color = name;
@@ -92,7 +256,7 @@ function nameToRGB(name: string): ColorRGB {
 // https://stackoverflow.com/questions/11068240/what-is-the-most-efficient-way-to-parse-a-css-color-in-javascript
 function parseColor(input: string): ColorRGB {
   // Hex format
-  if (input.substr(0, 1) === "#") {
+  if (input[0] === "#") {
     const collen = (input.length - 1) / 3;
     const fact = [17, 1, 0.062272][collen - 1];
     return {