Take existing ecommerce header and insert into wordpress (blog) theme

We are an e-commerce online store (magento). We have been operating since 2005 and have a very large business footprint. Our blog is setup in Wordpress > currently the user is taken to a blog that looks and feels different to the ecommerce store. I want the header of our wordpress blog to look and function the same as the magento store. This will enable readers to navigate back to their cart and the ecommerce store if wanted. I want the CSS of the blog to be as close to the styling of our ecommerce store as possible. I have the Wordpress theme we have chosen and access to all Magento elements. I have basic web design, graphic design and CSS skills, so you are not working with a complete novice. The wordpress theme is new and the magento site is existing. Only the wordpress theme can be changed Also, this is the theme I have chosen [login to view URL] this is my magento site [login to view URL]