What do you clean your tile shower walls with if your cat drinks from the puddles?

My cat jumps into the shower as soon as I’m done. He even slides open the doors when I’m not home and jumps in to drink up some puddles. (He has a regular water bowl that he uses but still insists on finding other ways of keeping hydrated.)

I need to keep the tiles clean, but I’m afraid that anything I use will be ingested by the cat. Is there a safe cleaner to use?