How to add graphic elements that are tied to text and adjust for mobile

Hi! I want to add graphic elements that stick to text. In the mockup image uploaded here, you'll see a purple oval shape behind "UX/Visual." I want that to always sit behind the "UX/Visual" text. I haven't been able to figure it out with the poster image block and I wonder if anyone has any other ideas. The tricky part seems to be making it stick to that text specifically, especially between different screen sizes. Right now I have the oval as a PNG and the text is normal page text. Not sure if there's a way to do it without an uploaded image. Any advice greatly appreciated! Would love to know more about adding graphic elements like this in general.

Hi. What is your site url?