Modify webMethods Integration Server Statics Page With a Countdown

webMethods IS used and 10.7 version level:

We have a cloud license lease which needs to renewed every 180 days, is there any way we can modify our IS statics page to shows us a countdown for expiry.

I think it can be done by modifying webMethods.css file under WmRoot, could you please suggest if it’ll cause any issue in case we modify this file or is there any other better way to achieve this.

Question related to a free trial, or to a production (customer) instance?