Use the class mzp-t-warning for a cautionary notification, to indicate something may be risky but the user can choose to proceed. This example also features a close button (the button isn’t functional, it’s just for demonstration).

<aside class="mzp-c-notification-bar mzp-t-warning">
    <button class="mzp-c-notification-bar-button" type="button">Close notification</button>
    <p>Warning! It's dangerous to go alone.</p>
</aside>