One of the most exciting new features of NetNewsWire 2.0 is definitely the support of custom stylesheets, providing you with a way to style the content in your favorite way. As NetNewsWire uses Safari's rendering engine and standardized CSS to render the feeds' contents, it's quite easy to create custom stylesheets.
Aqua and graphit
I really enjoy apps that stick closely to Apple's design guidelines
an thus integrate themselve perfectly in the look&feel of Mac OS.
NetNewsWire's integration is nearly perfect — except for the bunch
of stylesheets, which are included by default. So I decided to create my own
ones, especially focusing on the two default styles of Mac OS: aqua and
graphit. Both of the styles are available in a floating and a fixed version;
the “fixed” version uses the CSS property position:
fixed in order to prevent the header, as well as the info area from
scrolling.

In order to install the styles first make sure that you have installed at least beta 2.0b22 and double click the respective nnwstyle file. This should bring up a dialog asking if you want to install the stylesheet. Confirm and select the respective style from the dropdown menu in the bottom right corner of the application window.
Alternative icons
Also included in the package — two alternative application icons; one using the graphit style, the other one held in aqua blue. So depending on your system settings, you can either style your whole application in aqua or graphit style. In order to use an alternative icon instead of the original one, just download the package and rename the intended icon to “appIcon.icns”. Afterwards copy the file in the resources folder of your NetNewsWire app — most likely this will be “/Applications/NetNewsWire.app/Contents/Resources/” — and restart the application. The new icon should appear in the finder, as well as in the dock.

