Changing color of the shopping card in various pages

[Maltauschen21]

Hello there!

I want to change the background color of the shopping card button to the following color: #CE2D4F

I managed to do so in the collection pages by adding the following code to base.css 

.quick-add__submit {
background-color: #ce2d4f;
color: #f6e7f2;
} 

However, when clicking on other pages (Product page or shopping card) the color is still the old one.  How can I fix this? 

Also if it is not that complicated, would it be possible to change the color to a light grey when the product is sold out? 

The link to the website is the following: www.salufarmashop.com

Thank you

[stefansweb2020]

button.product-form__submit {
    background-color: #ce2d4f;
    color: #f6e7f2;
}

Here is how