WordPress Enqueuing Styles Add Alternative Stylesheets
Example
<?php wp_enqueue_style('theme-five', get_template_directory_uri() . '/path/to/additional/css');
wp_style_add_data('theme-five', 'alt', true);
wp_style_add_data('theme-five', 'title', __('theme-five.css', 'your-theme-name')); ?>
