For a website, you need to have an idea, you need to have a design and you need to have data, events and output, right? Whether it be a blog, web app, Q&A site, search engine...
Anyway, that is only slightly related to my question. My question is, when designing a website, providing I know the purpose, what should I start with?
Should I start with the CSS, design and look&feel using dummy data first, or should I program in the logic, events and output, and style it later? What is the design process of most websites that are built from the ground up?