On the dark side of Venus, the sky wouldn't be a uniform black like it is on a clear night on Earth. Instead, it would have a faint, mysterious glow. This phenomenon is known as the ashen light and is a subject of ongoing scientific debate. The color of this glow is often described as a coppery brown or a dull rusty color.

https://archive.org/details/venera-14-venus-recording

On the night side, these oxygen atoms combine, releasing energy in the form of a faint glow. This is similar to the airglow or aurora effects seen on Earth, but it's a constant glow rather than a flashing light show.

While this glow would be present, it's not strong enough to illuminate the surface significantly. Therefore, the ground would still be very dark, with the glowing atmosphere overhead.