How do I get the red heading + black sub-category in the menu?

To resolve this issue, you can add the following code to the style.css file:

.navbar .nav { 
    background: #ff0000;
}
.navbar-inverse .navbar-inner {
    background: #ff0000;
}
.navbar .nav > li > .sub-menu > li {
    background: #000; 
}
.navbar .nav > li.has-sub-menu:after {
   border-color: #000;
}
.navbar .nav > li > .sub-menu a {
    color: #fff;
}
.navbar .nav > li > .sub-menu li .sub-menu > li {
    background: #000; 
}
.navbar .nav > li {
    border-color: #fff;
}

– If you still face there issue, you can send me a screenshot for further checking. 
Hope this helps !