It's difficult to provide guidance without seeing the code you're working with, but some of the desired effects can be achieved using CSS. It appears that a background image may have been added to one of the tabs.
Have you tried using developer tools to analyze the code and understand its purpose? This could be a helpful starting point for your own implementation.
Remember to consider language barriers and be patient with those who may not have English as their first language. It seems like the goal is to replicate the blurred background image effect seen on the website.
Another approach could be to design the element in Photoshop and then incorporate it into the CSS through images.