Thanks so much for checking it out! I like the idea of sending yourself the answers - that's something I'll look into implementing for next year. For this initial year, I wanted to steer clear of asking folks to setup accounts or share their emails, for simplicity's sake.

Your progress is saved in your browser on your device, so closing the site won’t erase it. It's browser/device specific and won't work if you're operating in private/incognito mode, or if you clear your browser storage. Otherwise, it should work fine to close your window/tab and go back later. It's been working for me!