Is it legal...?

NO, it is NOT legal. Tinted headlights and "smoked" tail lights are also NOT LEGAL. Just because you don't get pulled over every time you go for a drive DOES NOT mean that your modifications are legal to use.

Google search is a wonderful thing.

It is illegal

as long as the plate can be read at the official distance I don't see why not

It might be legal, but do you really want to have a cop pull you over by the side of the road to tell you about why they think it's not legal? Once they see the plate cover, they might pull you over and give you a hard time until they find something else you have done that's worthy of an expensive ticket (revenue for the state).

Illegal

"It shall be the duty of the operator of any vehicle to keep the license plate legible at all times. No license plate shall be covered with any material unless the material is colorless and transparent. No apparatus that obstructs or hinders the clear display and legibility of a license plate shall be attached to the rear of any motor vehicle required to be registered in the state. Any person who violates any provision of this Code section shall be guilty of a misdemeanor."

no