I don't think it's necessary to fade out the header and sidebar. The layout is simple enough that having those components at full opacity shouldn't be overwhelming.

Also, while the fully-justified body text produces nice, straight left and right edges, notice that because it's not a very wide column you get some significant spacing between words. If you want to keep it this way, you might look into using a hyphenating javascript library, which will help with the rhythm of the text.