Responsive Web Design

1. When setting flexible margins on an element, your context is the width of the element's container. 2. When setting flexible paddings on an element, your context is the width of the element itself. Which makes sense, if you think about the box model: we're describing the padding in relation to the width of the box itself.

But most importantly, responsive web design isn’t intended to serve as a replacement for mobile web sites. Responsive design is, I believe, one part design philosophy, one part frontend development strategy. And as a development strategy, it’s meant to be evaluated to see if it meets the needs of the project you’re working on. Perhaps there’s a compelling reason to keep your site’s desktop and mobile experiences separate, or perhaps your content would be better served by a responsive approach. Only you and your users know for certain. While I agree with mobile web designers who say that certain users of certain sites deserve different content, I think the reverse is also true: many sites can benefit from serving one document up to multiple contexts or devices. And those are perfect candidates for a responsive approach.