Whenever my link references my index.html, it ignores any text-decoration settings and turns purple

Hello,

I have a link in a file called ridiculousstudios.html, and the link references index.html, another file in my website. However, whenever that link references index.html, it turns purple, even if my css for the link sets all text-decoration to none. If I change the link to reference something else, it will turn the appropriate color.