Oh thank you very much!
I am so sorry if "robe" isn't the correct word in English (which isn't my first language) and if I made it confusing. I will check it out and correct the zine, so thank you for pointing it out!
In this context, I meant "robe" as in "the colour of the liquid in the cup". So black tea has this rich, red-brown colour, while green tea might have a clearer, yellow-ish or green-ish colour.