Hiding CSS not applying to only some products?

I have a store where some of the items are categorized as "Shapeways" items.

I have css that hides their price, as well as purchase button however for reason, the moment I edit the product in the slightest, the css no longer applies and everything is revealed again.

// Remove SOLD OUT on Shapeways //
.category-shapeways .sold-out,
.category-shapeways .is-sold-out {
  display: none !important;
}

.category-shapeways {.sqs-add-to-cart-button {
  display: none !important;
  background: none;
  color: #fff;
  border: none;
  text-align: center;
  }}

.category-shapeways {.ProductItem-product-price {
    display: none !important;
}}

Can anyone help explain why? I don't alter their category tags at all. I can just go into the product info, add a space in their description and suddenly the css no longer applies to them anymore.

One problem product is: https://www.pashapashanewyork.com/shoes/p/vortex-shoes

Do you still need help?

I am trying to do a similar thing since the template seems to add an "Add to Cart" button that I do not want. In addition the max price is 1000000e and I would like to increase it. Is it possible with code injection?