What do you mean by "the fifth century is prosperous, dragons and phoenixes become auspicious"?

First of all, there is a typo, not auspicious, but "auspicious dragon and phoenix" In the picture, the dragon and the phoenix live in half. The dragon is a rising dragon. Open your mouth and turn around and look back at the phoenix. Phoenix is a auspicious peak, spreading its wings and raising its tail, looking up at the dragon. There are many clouds around, and there is a peaceful atmosphere.