How to disable default wp-bannrize style?

Hello all!
Thanks for making great plugin.
I have a question.

How to disable “wpBannerizeStyleDefault.css” ?

I tried this on my theme’s functions.php

function deregister_plugin_style() {
    // OK
    wp_deregister_style('contact-form-7');
    // NG
    wp_deregister_style('wp-bannerize');
    wp_deregister_style('wpBannerizeStyle');
    wp_deregister_style('wpBannerizeStyleDefault');
    wp_deregister_style('kWPBannerizeBannerStyleDefault');
    wp_deregister_style(kWPBannerizeBannerStyleDefault);
    wp_deregister_style('WPBannerize');

  }
  add_action('wp_print_styles', 'deregister_plugin_style', 100);

but I can’t disable wp-bannerize default style.

My environment:

• WordPress 3.9.3
• wp-bannerize 3.1.6

Please tell me!
Cheers,
Yoshi.

https://wordpress.org/plugins/wp-bannerize/