The colors depend on your color scheme (.tmTheme) and the scope of the syntax file (.tmLanguage). If your theme colors the scope "keyword" red (for example), then you could use that "keyword" as the scope in your tmLanguage for "01".
To simplify my life I use add "color.red", "color.blue", etc. in my own tmTheme. But there is no convention for this that I know of.
All in all, the process is a little messy.