Code increasing banner bg size

I'm not sure why this would happen but on my laptop my background banners size has increased compared to my desktop view. I got into contact with squarespace and they said it could be because of the code and to remove the code and see if it fixes it - it did. It is due to the code of the big title. Do I need to make the font smaller? Is there a reason it is not laid out like the desktop version? I've attached the code I used for the font below) 

first image is of my desktop, second image is of my laptop and third image is when all the code from my website has been removed