shine "bright" / "brightly"

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hello Alan, Mister Micawber, Beeesneees, Mordant, Esl_Expert and other native English speakers,

downunder-dago.com/113/Travelogues.html
The beach was filled with people on this day and the sun was shining [color=red]bright.

Isn’t “brightly” correct? Is “shine bright” an idiomatic expression?

2

According to the dictionaries, “bright” is both an adjective and an adverb, so you don’t have to add “-ly”. You can do it if you want, but it’s not necessary.

3

Thank you, Jamie.