It does not appear to be PageLines related, as nothing PageLines does, or can do, will result in a Service Unavailable message when trying to access a WordPress login page. This is strictly a plugin issue, which, as I said in Live chat, is likely related to code written by a plugin to your .htaccess file. Keep in mind, before PageLines has even loaded, the /wp-login.php redirects to your domain.
While the CSS for the store items may be related to PageLines, it is more likely related to WooCommerce. Either way, it is impossible to determine without being able to view every one of the possible elements. Please understand there are tens of thousands of lines of code in PageLines, and doubtlessly more in WooCommerce. We can't remember every line of CSS for every plugin. I'm sorry about that, but we'll be happy to view the site when it's accessible, and will gladly help you identify the CSS and changes that are needed.