A dropdown menu is a toggleable menu that allows the user to choose one value from a predefined list
The .dropdown-divider class is used to separate links inside the dropdown menu with a thin horizontal border
The .dropdown-header class is used to add headers inside the dropdown menu
The .active,.disable class is used to add headers inside the dropdown menu
To right-align the dropdown, add the .dropdown-menu-end class to the element with .dropdown-menu
The .dropup class makes the dropdown menu expand upwards instead of downwards
Trigger dropdown menus at the right of the elements by adding .dropend to the parent element
Trigger dropdown menus at the right of the elements by adding .dropstart to the parent element