Learn how to create callout messages with CSS.
Read on how to do it in this link: https://www.w3schools.com/howto/howto_js_callout.asp
Callout
A callout message is often positioned at the bottom of a page to notify the user about something special: tips/tricks, discounts, action needed, other.
Try it yourself here: https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_callout