I couldn't find a list of color codes, so I created this.

Testing area

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White

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  – Use #FFFFFF

Black

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  – Use #000000

Gray

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  – Use #EEEEEE
  – Use #DDDDDD
  – Use #CCCCCC
  – Use #BBBBBB
  – Use #AAAAAA
  – Use #999999
  – Use #888888
  – Use #777777
  – Use #666666
  – Use #555555
  – Use #444444
  – Use #333333
  – Use #222222
  – Use #FF3333
  – Use #FF2222
  – Use #FF1111
  – Use #FF0000
  – Use #EE0000
  – Use #DD0000
  – Use #CC0000
  – Use #BB0000
  – Use #AA0000

Pink

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  – Use #FFEEEE
  – Use #FFDDDD
  – Use #FFCCCC
  – Use #FFBBBB
  – Use #FFAAAA
  – Use #FF9999
  – Use #FF8888
  – Use #FF7777
  – Use #FF6666
  – Use #FF5555
  – Use #FF4444

Magenta

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  – Use #FF009F
  – Use #FF008F
  – Use #FF007F
  – Use #FF006F

Maroon

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  – Use #9F0000
  – Use #8F0000
  – Use #7F0000
  – Use #6F0000
  – Use #5F0000
  – Use #4F0000
  – Use #3F0000
  – Use #2F0000

Orange

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  – Use #FFAA00

Yellow-Orange

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  – Use #FFDD00

Yellow

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  – Use #FFFFEE
  – Use #FFFFDD
  – Use #FFFFCC
  – Use #FFFFBB
  – Use #FFFFAA
  – Use #FFFF99
  – Use #FFFF77
  – Use #FFFF66
  – Use #FFFF55
  – Use #FFFF44
  – Use #FFFF33
  – Use #FFFF22
  – Use #FFFF11
  – Use #FFFF00
  – Use #DDDD00
  – Use #CCCC00
  – Use #BBBB00
  – Use #AAAA00
  – Use #999900
  – Use #888800
  – Use #777700
  – Use #666600
  – Use #555500
  – Use #444400
  – Use #333300
  – Use #222200

Gold

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  – Use #FFD700

Yellow-Green

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  – Use #DDFFAA
  – Use #DDFF00
  – Use #CCFF00

Green

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  – Use #EEFFEE
  – Use #DDFFDD
  – Use #CCFFCC
  – Use #BBFFBB
  – Use #AAFFAA
  – Use #99FF99
  – Use #88FF88
  – Use #77FF77
  – Use #66FF66
  – Use #55FF55
  – Use #44FF44
  – Use #33FF33
  – Use #22FF22
  – Use #11FF11
  – Use #00FF00
  – Use #00EE00
  – Use #00DD00
  – Use #00CC00
  – Use #00BB00
  – Use #00AA00
  – Use #009F00
  – Use #008F00
  – Use #007F00
  – Use #006F00
  – Use #005F00
  – Use #004F00
  – Use #003F00
  – Use #002F00

Blue

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  – Use #CCDDFF
  – Use #EEEEFF
  – Use #DDDDFF
  – Use #CCCCFF
  – Use #BBBBFF
  – Use #AAAAFF
  – Use #9999FF
  – Use #8888FF
  – Use #7777FF
  – Use #6666FF
  – Use #5555FF
  – Use #4444FF
  – Use #3333FF
  – Use #2222FF
  – Use #1111FF
  – Use #0000FF
  – Use #0000DD
  – Use #0000CC
  – Use #0000BB
  – Use #0000AA

Turquoise

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  – Use #CCEEFF
  – Use #CCFFFF
  – Use #44FFFF
  – Use #33FFFF
  – Use #22FFFF
  – Use #11FFFF
  – Use #00FFFF
  – Use #00DDDD
  – Use #00CCCC
  – Use #00BBBB
  – Use #00AAAA
  – Use #009999
  – Use #008888
  – Use #007777
  – Use #006666
  – Use #005555
  – Use #004444
  – Use #003333
  – Use #002222
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  – Use #00009F
  – Use #00008F
  – Use #00007F
  – Use #00006F
  – Use #00005F
  – Use #00004F
  – Use #00003F
  – Use #00002F

Purple

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  – Use #EEDFFF
  – Use #DDCEF0
  – Use #AA9BCC
  – Use #AA8BCC
  – Use #AA7BCC
  – Use #AA6BCC
  – Use #AA5BCC
  – Use #AA4BCC
  – Use #AA3BCC
  – Use #AA2BCC
  – Use #AA1BCC

Red violet

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  – Use #FF00FF
  – Use #DD00DD
  – Use #CC00CC
  – Use #BB00BB
  – Use #AA00AA
  – Use #9F009F
  – Use #8F008F
  – Use #7F007F
  – Use #6F006F
  – Use #5F005F
  – Use #4F004F
  – Use #3F003F
  – Use #2F002F

Brown

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  – Use #DDCEAA
  – Use #CCBD11

Peach

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  – Use #FFDCBB