Thank you! It's burlap -- I found a roll cheap at Walmart and stuck some eyelets in the corners, then threaded gardening wire through to hook it on. So, even if she messes it up I can just make a new one easy.
As for the bridge ladder, I just looked in the small animal/bird section on Amazon until I found something reptile-safe. Was tempted by those suspended coconut hides, but maybe next time.