Shenzhen Transit 11hours

Hi Borut, I am a Polish citizen and will be flying from Bangkok to Barcelona through Shenzhen on December 31st 2024. I have a layover 11 hours in Shenzhen. Can I get a visa at the airport that will allow me to go out and spend a few hours in the city and then return to the airport? Last year I flew from Barcelona to Bangkok also through Shenzhen and got a visa at the airport but I don't k ow which one was it and if it permitted me to gonout as I had a layover only for 6 hours and decided to stay at the airport. I would greatly appreciate any advice as I found it very difficult to find a specific answer anywhere. Thank you in advance!