Change or Remove ‘Customer Matched Zone’

If you see at the top, there is a large green bar showing that ‘customer matched zone’, I want to remove this or at least change the green colour to something more on brand. How can I do that?

Along the same lines, how can I also change the checkout page coupon code bar? Currently it is set to a bright blue colour, but I cannot find the coding in my css to change that – many thanks in advance!

The page I need help with: [log in to see the link]