Recently I had trouble removing all the inline CSS created by the Theme Customizer. As I like to use normal CSS files (with LESS & Grunt of course) I was desperately looking for a way to purge these evil lines.
After searching for over an hour I found that it’s as simple as putting the following code in your functions.php file:
add_action('init', 'remove_all_dirty_css');
function remove_all_dirty_css() { remove_theme_mods(); }
You only have to call this function once, so you can delete it after the first request.