CSS file slows down site load

Hello! Thank you so much for this plugin. I have one little issue with it—it loads render-blocking CSS above-the-fold in the file contentstcr-plugin-style.css.

The only content in that file is .hidden{display:none!important;} and it doesn’t appear to be used with my settings. Is there a better way to implement that code, and/or would it be possible for you to omit that file from future versions so our sites all load as quickly as possible? Thank you!