Example:
<div class="linked">
<button class="btn">Button 1</button><button class="btn">Button 2</button>
<button class="btn">Button 3</button>
</div>
<div class="linked">
<button class="btn">Button 1</button><button class="btn">Button 2</button>
<button class="btn">Button 3</button>
</div>
<div class="linked vertical">
<button class="btn">Button 1</button><button class="btn">Button 2</button>
<button class="btn">Button 3</button>
</div>
<div class="linked">
<input class="input" />
<button class="btn">Button 1</button>
</div>
When a button or an input is not a direct sibling of other button and input elements, it container must have a special wrapper class applied to correctly link together.
<div class="linked">
<button class="btn">Button 1</button>
<div class="btn-wrapper">
<button class="btn">Button 2</button>
</div>
</div>