Disable "Add to Cart" for custom product .json file

[lanakcustomflag]

I've seen instructions for adding a new custom product (liquid) file to disable 'add to cart' but my custom product template is .json. I need to remove the add to cart button from these pages:  https://www.customflags.com/collections/customflags/products/custom-flag

[Laura-Hirtop]

I can see that you added a property to the button "display: none;", but it is overwritten by the default css. I suggest to add this property to the parent element, the <div> above with the class "product-add-to-cart" and add an "!important" after: "display:none !important;". This "important" would overwrite the default customization, and it would be better to have the entire div hidden in order to be sure that the responsiveness is not affected.