Disused train station in Hamburg with star-shaped stones?

https://photos.app.goo.gl/vmVhqWN7MACaeKcg9 We have this train station here, maybe you know it. I find it interestingly done, and I think it's supposed to be art. But I'm not sure, and to be honest, I'm a bit lazy to research what it's all about and what it means. Maybe someone can explain it to me briefly. I also find the star-shaped stones interesting. Did someone turn each individual stone into a star?