The .dropdownclass indicates a dropdown menu. To open the dropdown menu, use a button or a link with a class of .dropdown-toggleand the data-toggle="dropdown"attribute. The .caret class creates a caret arrow icon (), which indicates that the button is a dropdown. Add the .dropdown-menuclass to a <ul>element to actually build the dropdown menu.

The .dividerclass is used to separate links inside the dropdown menu with a thin horizontal border:

The .dropdown-headerclass is used to add headers inside the dropdown menu:

To disable an item in the dropdown menu, use the .disabledclass (gets a light-grey text color and a "no-parking-sign" icon on hover):

To right-align the dropdown, add the .dropdown-menu-rightclass to the element with .dropdown-menu:

If you want the dropdown menu to expand upwards instead of downwards, change the <div> element with class="dropdown" to "dropup":

To help improve accessibility for people using screen readers, you should include the following roleand aria-*attributes, when creating a dropdown menu:

If you want the dropdown menu to expand upwards instead of downwards, change the <div> element with class="dropdown" to "dropup":