Welllll…. Without knowing the material it’s made from, here’s what I would do. First, try a water-dampened cloth warmed in the microwave. Start with gentle pressure and increase, maybe rub gently and see what the surface does. If that doesn’t work, I’d try a damp Magic Eraser, very gently. I’ve never had one stain something but it can mar the finish a bit, but nothing too horrible. That thing looks porous so I wouldn’t use strong or smelly chemicals for fear of it absorbing too much.

Or carefully try a baking soda/water paste.