How to Prevent Loading WP-DownloadManager's CSS File

Stop loading WP-Downloads CSS File

If you want to disable the WordPress plugin WP-DownloadManager‘s download-css.css file from being loaded, add the following code to your functions.php file:

remove_action('wp_print_styles', 'downloads_stylesheets');

Alternatively, if you would just like to use your own stylesheet, you can add a file named download-css.css to your theme’s directory, and the plugin will automatically load your stylesheet instead.