I love the Material Design Color System, but I hate typing the hexadecimal codes. I therefore decided to bite the bullet and spend some time converting the whole color system into CSS variables.
Check out the attached example.
Place the code at the head of your CSS file and replace your CSS colors like this:
border:1px solid #757575;
border:1px solid var(--gray-600);
I use VS Code and it gives a nice preview of the color.