website/_sass/post_content/_post_links.scss

.heading-links {
    color: $text-color;
    &:hover {
        color: $text-color;
        text-decoration: none;
        &::after {
            color: $grey-color;
            content: ' →';
        }
    }

    &:visited {
        color: $text-color;
    }
}

.post-link:visited {
    color: $brand-color;
}