Weed Weeps When Lights Go Off

I've noticed that when i turn the lights off my plants leafs start to weep, when i wake up to turn lights back on. they are flush back up looking beautiful, is that normal?

totally normal, every plant I have ever grown does this same thing...sign of a healthy plant is when it worships the sun ( leaves look like this :Y)

CK

Cheers mate, just wanted to check it over to make sure