Remove ADVERTISEMENT Label Added by Official Discourse Advertising Plugin

Problem: How to remove the ADVERTISEMENT text above ad banner when using official discourse-adplugin?

When we use the official Discourse Ad Plugin, the label “ADVERTISEMENT” in full caps is automatically displayed on the top left of all ad banners. Currently, there is no setting under the ad plugin to disable / hide / change the label.

Found similar problem from official discourse meta:

Our customers do not want ADVERTISEMENT in caps above the ad

Solution: Customize CSS to hide the ADVERTISEMENT label above Google AdSense, Google Double Click for Publishers (DfP) & Amazon Affiliates banners

Found the solution from official discourse meta:

Some sites require it, so it’s on by default. To disable, use the following CSS:
.google-adsense-label, .google-dfp-ad-label, .amazon-product-links-label { display: none; }