Buttons

See Bootstrap docs
<button class="btn btn-primary">Primary</button>
<button class="btn btn-secondary">Secondary</button>
<button class="btn btn-success">Success</button>
<button class="btn btn-info">Info</button>
<button class="btn btn-purple">Purple</button>
<button class="btn btn-warning">Warning</button>
<button class="btn btn-danger">Danger</button>
<button class="btn btn-light">Light</button>
<button class="btn btn-dark">Dark</button>
<button class="btn btn-sky">Sky</button>
<button class="btn btn-pistachio">Pistachio</button>
<button class="btn btn-darkblue">Dark blue</button>
<button class="btn btn-link">Link</button>

White button

<button class="btn btn-white">White</button>

Button sizes

<button class="btn btn-lg btn-primary">Primary</button>
<button class="btn btn-lg btn-secondary">Secondary</button>

<button class="btn btn-sm btn-primary">Primary</button>
<button class="btn btn-sm btn-secondary">Secondary</button>

Pastel buttons

<button class="btn btn-primary-pastel">Primary</button>
<button class="btn btn-secondary-pastel">Secondary</button>
<button class="btn btn-success-pastel">Success</button>
<button class="btn btn-info-pastel">Info</button>
<button class="btn btn-purple-pastel">Purple</button>
<button class="btn btn-warning-pastel">Warning</button>
<button class="btn btn-danger-pastel">Danger</button>
<button class="btn btn-dark-pastel">Dark</button>

Outline buttons

<button class="btn btn-outline-primary">Primary</button>
<button class="btn btn-outline-secondary">Secondary</button>
<button class="btn btn-outline-success">Success</button>
<button class="btn btn-outline-info">Info</button>
<button class="btn btn-outline-purple">Purple</button>
<button class="btn btn-outline-warning">Warning</button>
<button class="btn btn-outline-danger">Danger</button>
<button class="btn btn-outline-light">Light</button>
<button class="btn btn-outline-dark">Dark</button>

Hover shadow buttons

With a combination of multiple classes

<button class="btn btn-primary text-uppercase-xs hover-lift">Primary</button>
<button class="btn btn-secondary text-uppercase-xs hover-lift">Secondary</button>
<button class="btn btn-dark text-uppercase-xs hover-lift">Dark</button>
<button class="btn btn-success text-uppercase-xs hover-lift">Success</button>
<button class="btn btn-info text-uppercase-xs hover-lift">Info</button>
<button class="btn btn-warning text-uppercase-xs hover-lift">Warning</button>
<button class="btn btn-danger text-uppercase-xs hover-lift">Danger</button>
<button class="btn btn-light text-uppercase-xs hover-lift">Light</button>
<button class="btn btn-dark text-uppercase-xs hover-lift">Dark</button>
<button class="btn btn-sky text-uppercase-xs hover-lift">Sky</button>