This answer is going to be a little “tech-y”, but if you launch the website (I launched the link in the original post of this thread) in Chrome, you can right click anywhere on the page and choose “View Page Source” from the popup menu. Then, on line 10 of the code, there was the link to the style sheet (mystyle.css). You can click on that link and find the source code for the style sheet.
Hope that helps!
Mike