Should be easy peasy. You will likely land at the S gates, pass thru customs and pick up your bags, and then get on line to recheck them to SF. Next is TSA and getting to your probable A/B gate for the next flight. As long as your bags arrive expeditiously and TSA goes well, you should not need to rush, just keep moving.

Welcome to FT, LindaBeyce, we hope you stick around, learn some stuff and make some friends!