Exiting China Question?

Hello I'm Dan Dan I'm currently in China on a business visa the duration of stay is 60 days and I entered China on September 12th, 2017. I want to go to Hong Kong on November 10th, 2018 but I'm a bit worried because it's very close to the 60 days. Would it be okay if I left on the 60th day or will I be detained for it?