Hello,
You can use the next custom CSS code:
.st-menu {
background-color: white;
}
.mobile-nav .menu li a {
color: black;
}
.mobile-nav .menu li.current-menu-item > a, .mobile-nav .menu li.current_page_ancestor > a, .mobile-nav .menu li > a:hover {
color: #005dab;
}
add the code into Theme Options > Custom CSS
Regards