I want first Button to be in a focused state on page load

Hello,
I hope there is a fast way to solve this i just wanted to know on my websites mattress page i have 3 buttons each is a different mattress and when you select one it shows you the mattress image and the layers down below i have everything working however when the page loads or you go to the mattress page i want the first button (option) to be focused (selected) by default on page load. Can someone help me with that?

I have also attached an image as to how i would like when the page loads!


Here is the page link link: Mattress

https://preview.webflow.com/preview/dreamstar-project?utm_medium=preview_link&utm_source=dashboard&utm_content=dreamstar-project&preview=b4c2a7d068af4c9c8c9b636bb2e8dc37&mode=preview