Base-Apparael-coming-soon-page with HTML, CSS, and Javascript

I pushed myself to try new design techniques that I haven't used before i.e.: grid, picture tag, and mobile first design. I am happy with the way the mobile version of the site turned out, but I am having some issues with the desktop layout.

1. I am trying to say away from setting the picture on the right as a background image and using it as a component on the page itself. I am having problems with getting the image to resize at different screen sizes. Its either too large and extends out the parent or too small.

2. I would like the size of my <h1> to get large when the screen size gets larger. I'm happy with the sizing at mobile view, but I feel it's too small on desktop view.

If you have any feedback on how I can fix these issues. Please leave me a comment. I welcome any kind of constructive feedback I can get.