Zend - Linking CSS File

You can use either one of this below in your view file:

<?php
    $this->headLink()->appendStylesheet($this->baseUrl().'/css/style.css');
    echo $this->headLink();
?>

Or just use:
<link rel="stylesheet" href="<?php echo $this->baseUrl();?>/css/style.css"/>

Zend - Linking CSS File