Comment: 'new' tag CSS location

Once authenticated to your site, go to the help page. In the section 'How to format text in pages', select the link to 'basic codes', at codes/basic.php.

The code for new items is demonstrated here. With Firefox, select the line that includes the word 'new'. Right-click. View selection source.

Kazaa! it looks like the following:

Our newsletter has been published!  <span class="flag">new</span>

The style you are looking for is .flag.