Every color contained in an object with its corresponding hexa value for O(1) time lookup, find function below object

color object

var colors = { 
  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' 
};

var getHexa = colorString => colors[colorString.toUpperCase()] ? colors[colorString.toUpperCase()] : 'color not found';