Why is my galaxyS5 screen blacked out?

I was listening to Pandora and my galaxy S5 active blacked out and has not lit up since. It rings but the screen stays black.

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/ask-question/758225-why-my-galaxys5-screen-blacked-out-new-post.html
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