The mark consists of Color is not claimed as a feature of the mark. The mark consists of a yin-yang symbol. The mark consists of three circles: two small circles with radii equal to r and a large circle with radius equal to 6r. The two small circles are centered in the middle of the large circle from left to right and at distances equal to 1.5r from the top and the bottom edges of the large outer circle. The mark also consists of two medium half-circles with radii equal to 3r that are concentric with the two small circles. The top half-circle is convex outward to the right, and the bottom half-circle is convex outward to the left. The half-circles intersect each other smoothly at the exact center of the large circle. The colors are filled such that the left-side region that is bounded by the two half-circles is filled with the same color as is the lower small circle; the right-side region that is bounded by the two half-circles is filled with the same color as is the upper small circle.