Could you please create separate topics for different questions to prevent misunderstanding?
Please try this code
.single-product .product-information .cart .button:hover {
background-color: white;
}
seems there is a bug with Theme Options > Styling > WooCommerce > WooCommerce buttons on Single Product Page hover background option, so you may use custom code as a temporary solution. The problem will be fixed in next theme update.
Regards