This is the 16548th most frequent Russian word.
светлый
Bright; light; clear.
The word 'светлая' is used as an adjective to describe the room, denoting that it is bright or well-lit.
У него светлая комната.
He has a bright room.
Here, 'светлый' metaphorically describes the day, implying it was happy or joyful.
Это был светлый день воспоминаний.
It was a bright day of memories.
In this sentence, 'светлые' refers to the color of her hair, indicating that it is light-colored.