@Bruce: You shouldn’t edit any core theme files like style.css, functions.php, index.php and so in. All the files inside ‘simple-catch-pro’ directory should be remained unchained. If you want to add additional css, then you can build child theme and add in. For child theme, refer to http://catchthemes.com/blog/create-child-theme-wordpress/ or you can add your custom css in “Appearance => Theme Options => Custom CSS” box.
Now, to revert back the original css. You can download Simple Catch Pro theme from your account at http://catchthemes.com/my-account and then unzip it. Then option style.css, copy the css and then paste it in that style.css that you have open it from “Appearance => Editor”.
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