Have a look at this Flow bathroom concept by Art-Tic Design Studio. It is based on the point that all the elements like a sink or a bathtub are fused with the surrounding floor and walls. The concept is so calming and relaxing! The floor and the walls are done in concrete and so are the elements. The concrete seems not to end at all. The bathroom looks so fen shui and stylish and eco-friendly, of course, as here some green plants grow. Calm green and grey colors add relaxation and the tub with a bookshelf of concrete calls to spend some time lying in the foam.