CSS: Fix incomplete `width`

While `width` was set on paragraphs (`<p>`), they were not set on other
tags in an article. This lead to `<ul>` tags and others tags not
wrapping correctly.

![screen shot 2013-06-20 at 00 24 13](https://f.cloud.github.com/assets/730342/678218/caba46ac-d92e-11e2-9fdb-3441ca7e4ed4.png)