Are cirrus and nociluent clouds dark below and above?

I noticed something unusual the sky was black, but it was a cirrus and nociluent overcast, the cirrus were as well as the nociluent when I looked, are they dark above as well, there was no cumulus but a lot of thin black clouds and even a tingish blue in some parts, it was dark out during the day, are black nociluent and cirrus clouds dark from above and below the atmosphere. I know cumulus are dark but was wondering if these clouds were, there was also orange lightning what is the cause of this?