I dropped my iphone in coffee, the sound still works but the screen is blacked out?

I dropped my iphone in coffee, the sound still works like if someone called or text me i can here it and when i hold my home button it goes to siri, but the screen is blacked out.yeserday on my way to the waterpark at 9;00 i droped my phone into my friends dads cup of coffee. It was only in there for two seconds and i toke it out dryed it with paper towels and being the idiot i was i started seening if it worked my playing music and going on kik. I sould have turned if off but i didn't. When i got home at 1:00 am i put it in rice till 10;30 in the morning. What do i do the screen is blacked out my my sound works fine.

Added (1). Seriously please give me a real answer!

If you drop it in milk the screen will turn white.

You should not turn on the phone bcuz it may dmg the circuit inside. Just leave the phone in rice bag for at least 20hours

I was walking then I saw a squirrel ***!