Examples
Default styling
.btn-lg
Large sized button
.btn-sm
Small sized button
.btn-xs
Extra-small sized button
.btn-block
Block sized button
Markup
<div class="row">
<div class="col-xs-12 col-md-6">
<button class="btn btn-primary [modifier class]">Button Element</button>
<input class="btn btn-secondary [modifier class]" type="button" value="Input Button" />
<input class="btn btn-tertiary [modifier class]" type="button" value="Tertiary" />
</div>
</div>
Source:
components/_button.scss, line 65