Customize mobile template for Big Commerce website.

Current website uses Big Commerce. It's a dark/black theme with orange and white lettering. However, the mobile theme doesn't match. It is all white with black lettering and very boring. I have already added an image to the header on the mobile template, and changed the main navigation elements black. WHAT I NEED: I need someone to finish the work I started. I need the mobile theme to be similar to the main(non-mobile) theme. We need to remove the prior "white" elements and replace with black with orange and white lettering. Additionally, I need the header image to be full width with no padding. Once these changes are made, I need to make sure everything is formated, legible and functioning.