1to shine or glow; to be illuminated or reflected attractively — to appear bright or striking due to light.
ネオンが夜の街に映えている。
The neon lights glow against the night city.
街灯に照らされて、川面が映えて見えた。
Illuminated by streetlights, the river surface looked radiant.
キャンドルの光で顔が映える。
Her face was lit up by the candlelight.
2to look attractive or stand out (often because of contrast or background); commonly used as '... ni haeru' or in 'photogenic' contexts.
白い壁に赤い花がよく映える。
The red flowers stand out well against the white wall.
そのドレスは青い海に映えて写真映えする。
That dress looks great against the blue sea — it photographs well.
冬の白い雪に緑の木々が映えて美しい。
The green trees look beautiful against the white winter snow.