Question about Pure Chronos CD Series 2

I was surprised by the brightness of the LCD screen. The green writing doesn't bother me, but the green background at night does. It prevents me from sleeping. Because even when it's off, it lights up the whole room. I looked for a way to program it differently, but I couldn't find it. The only thing I have managed to do is to dim it slightly. If anyone can help me it would be great...