Wikipedia has a good section on the different methods of describing colour: https://en.wikipedia.org/wiki/ANSI_escape_code#3/4_bit

I've got some Go code that you can reuse if you want to the escape codes in Go: https://github.com/lmorg/murex/blob/master/utils/ansi/codes....

Just bare in mind that any numbers you see in documentation are sent as ASCII values rather than integers. eg `ESC[31m` (red text) should be sent to the terminal as

    []byte{  // http://www.asciitable.com/
        27,  // ESC character code
        91,  // '['
        51,  // '3'
        49,  // '1'
        109, // 'm'
    }

Though, as you know, most languages will have some syntactic sugar to translate characters to their ASCII values, eg

    'm' == 109
    Asc("m") == 109
    ...etc...

so at least you don't have to write all those values by hand.