Alternatives to covering crate?

Our 6 month old lab does pretty well in her crate majority of the time. We cover the crate with a crate cover to make sure it stays dark for her during the day. Lately she has been pulling the blanket through and chewing it. I’m concerned about the fabric she is eating, and no matter how we lay the cover on she always manages to pull it through the crate. Is she old enough now to remove the blanket cover altogether? Any alternative ways to keep the crate dark so she sleeps better during the day?