Then I finished off the edges with quarter round molding. (tarynwhiteaker.com)
After my epic hunt for trim was a bust, I finally bought two sticks of quarter round because third grade math taught me that two quarters equal one half. (froufrugal.com)
For the black along the walls, as your husband and others have suggested, quarter round around the base of the trim would solve that problem. (hookedonhouses.net)