California base overtime schedule is 1x for 8 hours in a day, 1.5x for the next 4 hours in a day, then 2x for any time after that. Additionally, any time above 40 hrs in a workweek or on a 7th day of consecutive work in a workweek gets 1.5x, and any time after 8 on that 7th day gets 2x.

Thus, it's possible to only get paid your base rate for 16 hours in a workweek, if you work more than 40 hours in the first 2 days of the week. For example, if I worked 24 hours on Monday, and 16 hours on Tuesday, I'd be making 1x * 8hrs on Monday + 1.5x*4hrs on Monday + 2x*12 hours on Monday, then 1x*8hrs on Tuesday + 1.5x*4hrs on Tuesday + 2x*4hrs on Tuesday. On every subsequent day of that week, my standard workday would be paid at 1.5x for the first 12 hours, then 2x for any time after that, until the seventh consecutive day, where I'd get 1.5x for 8hrs, then 2x after that.

All together, in California, if you work 24/7 for a week, you end up with

16hrs@1x + 64hrs@1.5x + 88hrs at 2x, netting out to an effective 188hrs per week.

IMO, this whole system is a little busted owing to the fixed workweek (it's not "any 7 day period", it's "over the course of a recurring 7 day schedule")