Buttons or links wrapped in a container with class (.btn-group)
Create a group of checkboxes or radiobuttons. The checkboxes must have the class (.btn-check), labels linked to the input, and autocomplete off.
Combine button groups within a div of class (.btn-toolbar) to create toolbars.
To size buttons, just add the appropriate class to the button group container, not the buttons.
To group the buttons vertically, use class (.btn-group-vertical)