You might want to assign this before you plot the data.
E.g., make a column in your dataframe with the name of the color (or color value), and use dplyr::case_when
to conditionally assign the color based on some condition.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…