My (20M) girlfriend (20F) of 2 years insists on hiding her body during sex. How can I help her feel more comfortable?

Hey everyone, I’ve been with my girlfriend for 2 years and things are great, but I’m a bit confused about one thing.

Every time we have sex, she insists on the lights being pitch black. She also constantly pulls the covers over us, even if it’s super hot in the room. It feels like she’s trying to hide her body the whole time.

The thing is, she’s beautiful and there’s absolutely nothing "weird" about her body. I tell her she looks amazing all the time, but she’s still so shy. After 2 years, I thought she’d be more relaxed around me by now.

When I ask her about it, she just says she "feels better" that way. I don't want to pressure her, but it feels like there’s a wall between us.

Has anyone else dealt with this? How do I talk to her about it without making her feel even more self-conscious?