The emails sent from the theme can be managed from Theme Options > Advanced > Email Management.
You can leave blank the subject field and the notification will NOT be sent. This applies to any notification from Theme Options > Advanced > Email Management.
The email management text area has Visual Editor and Text Editor. In Text Editor, you can use inline styles, add the style attribute to the relevant element. The style attribute can contain any CSS property. Also, you can use text mode and <br> tag for new line.
To avoid losing HTML code use text mode and <br class=””> tag for new line, <p class=””> for a new paragraph, <span class=””> for styling.