How do I hide the price in Marketpress

Hi Guys I want to hide product price in the product page and in the category page (where all the products are displayed) I found the following code and worked like a charm:

.mp_product_price {
display:none;
}

but it doesn't hide the price in the category page just in the product's page, can you help me with the other code?

Also what code can hide the buy now buttons in both category and product page?

Thanks