Turn a button into a dropdown toggle with some basic markup changes.
Custom bootstrap buttons with icons
Create block level buttons—those that span the full width of a parent—by adding .btn-block.
Wrap a series of buttons with .btn in .btn-group.
Combine sets of button groups into button toolbars for more complex components.
.btn-group within another
.btn-group when you want dropdown menus mixed with a series of buttons.
Make a set of buttons appear vertically stacked rather than horizontally. Split button dropdowns are not supported here.