OBS Set-Up

Using OBS create a browser source.

Add the dimensions (Width:1920 / Height:1080)

Paste in the Link:

https://terrierdarts.co.uk/obs_links/sonic_one_alerts/index.html

Tick Allow OBS to control the audio.

Codepens

If you need to make any adjustments the original pen is here.

My Codepen : https://codepen.io/terrierdarts/pen/JjazQqy?editors=0111