The safe highest temperature is 113 C. Remember this is the max safe number. The ideal temp range for the transmission is 70 C to 90 C.
Just like you don't want the temperature to reach very high, the same applies to low temperatures. You shouldn't thrash the transmission with high rpms until it reaches operating temperatures. At least 60 C. Hard accelerations on cold CVT have high risk of belt slipping. From my experience of monitoring the CVTF temps closely, I have noticed it takes about 20~30 min of gentle driving to reach the CVTF temp to operating temperatures, i.e. 60~70 C.
Now coming to what different driving conditions and the temperature.
For city driving, CVTF temp stays between 90~95 C even in extreme heat in bumper to bumper traffic. Which is ok and safe.
On motorways, when driving at 4000 rpms or higher (which means you are racing) will raise the temp crazy high. The best rpm range for safe temperature is less than 3000 rpm on motorways.
On normal hills, specially if you drive for prolong time, they do get quite high, sometimes touching 100 C. But that's still ok.
When driving on very steep hills, specially at low speeds, the temperature usually crosses 113 C. The road from Kiwai to Shogran steep and there was no road after 2 km. So I had to drive in S mode at speed of 20 kph for 45 min. These were the conditions when my temp reached 116 C and I turned off the vehicle for 10~15 min to let it cool down.
The same happened when I was coming back from Shogran to Kiwai. You may wonder how could this happen when going downhill? CVTF temps do get high the same way on downhills as it does on uphill when using a lot of engine braking in L mode because it keeps the rpms very high. This is the reason engineers don't add aggressive engine braking with CVTs. A lot of people complain about weak engine braking with CVTs. It's done intentionally to save the transmissions.
