Is it haram to talk to a guy online as friends?

i have a friend who is a male online and we text and sometimes play games together. i have no intention of being anything more than friends and i know i have a strong mind which can refrain from it. we have never seen eachothers face and sometimes we call while playing games but thats it and we only call so we can play the game and have more fun and talk about the game instead of texting. can someone who is well educated tell me if being friends with the opposite gender is haram? and if it has been said in the Qur'an? i have tried searching for answers but everyone gives me a different answer.