A flat keyboard arrangement includes a color of blocks. Each block corresponds to a key unit and is liquid crystal display having a screen divided into a number capable of producing any natural color. A table is provided for storing color data of the blocks, and for storing function data representing the function assigned to blocks. A driver circuit is provided for driving the color liquid crystal display to illuminate one or more colors in accordance with the data stored in the table. A transparent touch switch arrangement is placed on the color liquid crystal display. The transparent touch switch arrangement has transparent sheet in which a plurality of transparent touch switches are located correspondingly to the blocks of the screen to define touch keys.