Hello Hans,
I see that you have changed the Link Color in “Appearance => Customize => Colors” as #ffffff and that is causing the issue. So, can you reset that or change it to the color that you want for the link.
I see that you have already added Custom CSS for Header Menu, but for Menu toggle and cart icons color in menu, you can add the following CSS in “Appearance => Customize => Additional CSS” box:
.menu-toggle,
.dropdown-toggle,
.site-header-cart .menu-inline a.my-account,
.site-header-cart .menu-inline a.site-cart-contents {
color: #ffffff;
}
Regards,
Sakin