<a href="#" class="btn">button</a>
<a href="#" class="btn-rounded">button</a>
<a href="#" class="btn-small">button</a>
<a href="#" class="btn-small-rounded">button</a>
<a href="#" class="btn-large">button</a>
<a href="#" class="btn-large-rounded">button</a>
<pre><a href="#" class="btn">button</a>
<a href="#" class="btn-rounded">button</a>
<pre><a href="#" class="btn-small">button</a>
<a href="#" class="btn-small-rounded">button</a>
<a href="#" class="btn-large">button</a>
<a href="#" class="btn-large-rounded">button</a>
[class^=btn-small] { font-size: .8em }
[class^=btn-large] { font-size: 1.5em }
[class$=rounded] { border-radius: .3em }