Changing cart icon on NATIVE template

Hey there, I'm using the theme Native and the only thing left to change on the site is the cart icon. My client wants just the hairline cart w/ numbers and I thought nothing of it because I've always been able to change it but after reaching out to live chat, they said that Native supports "classic cart" only, but I could potentially change style or at least color with CSS. Any advice on this? I've attached the cart style as it is now. Thank you!