Difficulty styling alert-warning message

Hi,

I am trying to style the message “Please fill out required fields” that is being shown if a user tries to subscribe without entering email. However, I can’t seem to do it given there is redundant <p> tags and a same class name being added to the closing </p> tag. If you visit here https://i.imgur.com/y0wnxOm.png?1, you can see in the elements tab that there is an empty <p> tag inside of the message and a class added to the closing p tag. If you could solve this in the very next update, I would be super grateful!