Following yesterday''s interruption, Steam servers appear to be experiencing similar problems, but this is because to another reason. Based on Steamstat.us, the game coordinators and servers are down due to a routine maintenance that concludes every Tuesday.
Both video game coordinators, including those from CS GO, Steam, and TF2, are not responding, and they will likely continue until the maintenance is concluded. While the Steam Store, Community, and Web API are working correctly, other games are unresponsive.
If you want to see more information, check the Steamstat.us website. Valve is not affiliated with Steam.