fx-message

There are 3 types of messages:

Appearance

level says how important a message is, appearance how it is presented. Both can be combined. Every message gets the CSS class appearance-<name> (appearance-toast, appearance-banner) which you can style from your own CSS.

Also refer to the native <dialog> element (used with the fx-show/fx-hide actions) if more complex messages are wanted, styled content or button logic is required.