adjective
vivid
VIV-id/ˈvɪvɪd/
Producing a strong, clear impression on the mind or senses.
The poppy's vivid scarlet petals stand against the white background.

Etymology
Vividus meant “full of life.” This idea extends to colors that look fresh and lifelike, and to descriptions or memories that make a distinct, strong impression on the mind.
In context
they notice how bright and detailed the images still are. The vivid reds, blues, and golds help tell stories of saints and religious scenes