What does Zhu Yuanzhang mean by ordering Spring Festival couplets to be written in black on a red background?

Spring Festival couplets are practical for calligraphy and painting in daily life. "Spring Festival couplets began in Ming Taizu. "Zhu Yuanzhang first ordered to write Spring Festival couplets in Zhu paper and black ink, and named it" Wan Nianhong "because" red "and" Zhu "have the same meaning. Zhu Yuanzhang's intention is to pray for the long-term stability of the authoritarian regime. URL = 76 fnjjvlfn P5 cgyjwd _ _ gvjh3sibsyuu 6 TT 7 btu 0 otxpyejofvhfhnln n 8 yyy 7 syjsh 8 faiouuic 19 eqldrbet 3 tzk 7 _ OmotrxihSI _ Jda