Fixed layouts aren't future proof
As I mentioned, since the "table layout" days, I've had little call to use proportional layouts. Typically, I've been asked to code HTML and CSS that best matches a design composite that almost always measures 950-1000 pixels wide. If the layout was ever built with a proportional width (say, 90 percent), the complaints would have arrived quickly, "It looks different on my monitor". Web pages with fixed, pixel-based dimensions were the easiest way to match the fixed, pixel-based dimensions of the composite.
Even in more recent times, when using media queries to produce a tweaked version of a layout, specific to a certain popular device such as an iPad or iPhone (as we did in Chapter 2, Media Queries: Supporting Differing Viewports), the dimensions could still be pixel-based as the viewport was known. However, whilst many might enjoy the possibility of re-charging a client each time they need a site tweaked for today's newest gizmo, it's not exactly a future...
