The way to do that is to use something like
For example
[wrap=link-button][Link Text](http://meta.discourse.org)[/wrap]
renders as
and the markup is
<div class="d-wrap" data-wrap="link-button">
<p>
<a href="http://meta.discourse.org">Link Text</a>
</p>
</div>
and you can then style it in CSS using
[data-wrap="link-button"] {
a {
// styles for the link
}
}
You can change [wrap=link-button]
to any value you want like
[wrap=custom-button]
or
[wrap=home-link]
or
[wrap=foobar]
and then use that to target the link like the example above.