Here’s a SharePoint branding tip for the top navigation menu:

To change the background color for the top navigation flyouts via CSS using this .ms-topNavFlyOutsContainer { background-color:#000 !important; } will give you a black background but will still cause the background color to be different when the text size is smaller then the width of the largest text item in your flyout menu. For example:

To change this, just go to your master page and change the syntax for your top navigation from

<DynamicMenuStyle  BackColor=”#F2F3F4” BorderColor=”#A7B4CE” BorderWidth=”1px”/>  to <DynamicMenuStyle  BackColor=”#000000” BorderColor=”#A7B4CE” BorderWidth=”1px”/>.

This will give you the following desired affect:

Replace the color black (#000000) with the color that you’d like the top navigation flyout menus to have.