Searches for a specific file in /content by filename
<?php if($file = $site->file()): ?>
<a href="<?php echo $file->url() ?>">
<?php echo html($file->filename()) ?>
</a>
<?php endif ?>
<?php if($file = $site->file('myfile.pdf')): ?>
<a href="<?php echo $file->url() ?>">
<?php echo html($file->filename()) ?>
</a>
<?php endif ?>