Ask HN: Math courses for a self taught web developer?

I have a degree in Political Science. I've been out of school for nearly a decade now, and in that time my career has transitioned to web development (and some backend systems work as well but not a lot).

I hear over and over that math is important for Computer Science[0][1] (not saying that web development is Computer Science). I have no interest in going back to school as a full-time student and I think it would likely only hurt my career. So what are my options if I want to increase my math skills in a way that will help my day-to-day life? The only college math I've taken was linear algebra, which I did poorly at but I was a different person then and did not care. I have a basic understanding of algebra, geometry and trigonometry. I have never taken a Calculus class.

[0] http://devlinsangle.blogspot.com/2015/04/the-importance-of-mathematics-courses.html

[1] https://news.ycombinator.com/item?id=9308595