Build simple eCommerce website - selling pdfs documents

1. Require a mobile friendly eCommerce platform that can sell pdf books (see http://mrbruff.com/). Copy same/similar style website - - needs to be mobile responsive

2. To make the site simple to navigate and have a clean but modern interface (as above website)

3. Pdfs need a preview on some of the pages.

4. Two urls will be pointed to the one website built (www.psychologyzone.co.uk and sociologyzone.co.uk) - they need to look exactly the same but different colours example is here:

5. FAQ section which will have a parent category and then a sub-categories e.g Exam Tips > Memory - here I can upload pdf /web-link (example see : http://mrbruff.com/help/)