A pair of first guide lights are displayed side by side adjacent to an HUD display area with emitted light from first light sources, and a pair of second guide lights are displayed at the outer sides of the respective first guide lights with emitted light from second light sources. At least one of the number of lighting lights, the lighting cycle, and the lighting order of the first light sources and the second light sources is changed in accordance with a differential value between the current speed and a speed limit set for a road on which the vehicle is traveling.