The question is a bit unclear, but it seems like you want to change the color of the nav's dropdown from white to something else.
My suggestion would be to use your own stylesheet to customize elements that are not included in Bootstrap by default.
Remember to add your custom styles at the end of all other stylesheets, preferably in a separate file to avoid changing the stock Bootstrap files.
Check out this Fiddle for an example of the dropdown with black instead of white.
jsFiddle: Demo
I added a class called .mainNav
to the <ul class="nav nav-tabs">
to specifically target this navigation without affecting other dropdowns on your site.
Remember, you can always extend Bootstrap with your own styles if needed. It's important to organize your customizations in a systematic way.
While Bootstrap provides some options like .navbar-inverse
for black navbar or .btn-inverse
for buttons, there may not be a built-in option to invert colors for a specific element like the dropdown in this case.