customization - Changing colour of table in wordpresswoocommerce cart

I've been trying to change the background colour of the cart-header and its items. Even when I change the colours of the theme in the Customizer to a different colour, the brown background in the cart persists. I've been looking through similiar problems and tried adding custom css like:

body .woocommerce table.shop_table td {
    background-color: #ffffff;
} 

.woocommerce-cart table.shop_table thead {
    background-color: #ffffff;
}

.woocommerce-cart table.shop_table tbody tr {
    background-color: #ffffff;
}

and also specifically for what I inspected

.wc-block-cart-items__row {
    background-color: #ffffff; 
}

but I can't get it to work. Every second item in the card has a white background as desired, but the third, fifth etc. items are brown again. I tried to find something in the style.css file but there's no css in it, so I can't find the proper folder or file to change things in the direct file.

Can you guys help me out? I don't really want to use elementor because I don't like the cart they offer and I don't know any other free plugins that let you modify the cart page easily.

I'm currently working o a demobox: /

Kind regards, Matse