The square is moving. First, it tilts to the right side and then it tilts to the left side, like a seesaw of sorts.
True? No. The parts that make up the lines are actually just “drifting,” as in they seem to be just cycling colors in a certain direction. That drifting makes it seem as if the whole shape is moving, but the bigger part actually remains still. Focus on any element and it is not moving!