Messes up rest of site's formatting

Hi, this looks like a great plugin but unfortunately activating it messes up the styling of all the text on my site – paragraphs, hyperlinks, lists, text in other plugins. For example all my hyperlinks have changed from red to blue. I’ve deactivated it and that’s fixed the problem, but I’d like to be able to use this plugin. Any tips on how I can prevent it from intefering with my CSS?

Thanks,

https://www.ads-software.com/plugins/blog-manager-light/