Formatting buttons in MarketPress

So I have already changed the buy button on products to be a Paypal style button by making it an image.

I need to do the same (or at least make these buttons more visible (darker, easier to read on a white background, bigger text):

1) Update Cart (update_cart_submit on Review Checkout)

2) Checkout Now (mp_cart_direct_checkout_link ? on Review Checkout)

3) Login and Checkout (mp_login_submit on Review Checkout)

4) Continue Checkout (mp_shipping_submit on Shipping)

5) Confirm Payment (mp_payment_confirm on Confirm)

I know how to replace the buttons with an image on 1,3,4,5.

A) What is the name of the button for #2

B) I may not have time to photoshop the buttons, what CSS can I use to set the text size, font, color; button color, border color?