I had a time where I suddenly didn't have access to internet for 3 weeks, and I didn't get the chance to put steam properly in offline mode or anything, however

I had a time where I suddenly didn't have access to internet for 3 weeks, and I didn't get the chance to put steam properly in offline mode or anything, however it still worked completely fine during this time and didn't feel the need to phone home. If I had an xbox one, I wouldn't be able to play my single player games after at most 24 hours.