Rudimentary

I'm just getting started with Squarespace. With very little discretion when I set it up I randomly picked a design template. I didn't like it after a while, but I couldn't figure out how to pick a different one. So I mucked about with the styles to try and fix it and ended up in a dark place where I now hate my site. Is there a way to wipe the slate clean and start all over again from the beginning? Like a factory reset?