A method includes obtaining time information of a target area, determining a first color of a digital clock based on the time information, where the digital clock displays a time in a screen-off state, and displaying the digital clock on a display screen of a terminal device when the terminal device is in the screen-off state, where the first color is a second color when the time displayed by the digital clock is a first moment, where the first moment is in a first time interval, where the first color is a third color when the time displayed by the digital clock is a second moment, where the second moment is in a second time interval, where the first time interval is different from the second time interval, and where the second color and the third color are different colors.