How to hide price and cart from store on mobile version using CSS

I set up two stores on my website. One which is an actual store with prices and add to cart is visible and is meant for selling merchandise etc. And one which I use as a portfolio and an "Inquire for price" page (Where I want to hide price/cart etc).

I used the below CSS code, which I injected in the specific page and it seems to work on a desktop/laptop but doesn't work for mobile consistently. Meaning it would load without the price but when I go to another page and hit refresh, the price and cart will reappear. 

I also shared a live view of my mobile page to show how it looks on the phone.