Systems are disclosed for an optically clear keyboard that can be applied to a touch-sensitive display screen, for example, while mitigating distortion of the display. A color image index indicating warmcool and a color image index indicating lightheavy are formed as two coordinate axes and the colors located therealong, the make-up color image is classified and a make-up color image map produced, making it possible to achieve a make-up color image accurately and easily. The cell array edge zone is only arranged in an edge region of the cell array, adjoining at least one trench of the cell array, and being at least partially arranged below the at least one trench in the cell array. In some cases, each media content item in the first subset can satisfy specified selection criteria. A pair of fasteners are operable for fastening rear ends of the pedal members selectively and respectively to the slide seats and to rear end portions of the lever arms.