Multiple Interior lighting?

Hi, I'm new to the forums, I just had a few simple questions about itnerior lighting.

I live in the monterey county of california, and from what I was able to find, it is only illigal to have VISIBLE LEDs/NEONs while driving, they ARE legal at a stop. And as far as interior goes, as long as they are not visible and are not a distraction they are okay. Can anyone correct me or give me further links to this type of legal information?

Secondly, you guessed it, I want to install neons or LEDs in my car, which is a 2006 Scion xB. Basically, I want to put them near the feet under the dash or actually under the seats, just to create a light blue glow. Can anyone recommend some neons or LEDs? And what kinds are good? I want ones with a good glow, but not WAY too bright or too dim.

Also, Ive read the tutorial at https://all-neon-car-lights.com/ but I am still afraid of screwing something up. Is it possible to wire it to my cigarette lighter? Since that is something I'll probably never use. But I just want these lights to turn on with my headlights.

Lastly, I use cold cathodes in my modded computer, and was wondering if I could buy the same thing, and just cut off hte molex connector on the end? Most of these have inverters (for the computer cathodes at least...), are they supposed to have these? https://www.xoxide.com/bluecathode.html

Sorry for the bunch of questions. I hope someone can answer these for me, THANKS!

xoxide and oznium.com both sell them with the transformers. so you can use them in car. (oznium shipping is less.)