Feed Styler enables you to keep your existing styles for your post, but allows a different style to be applied to the feed.
The plugin will accept most CSS. There are several things it can’t do, however.
Feed Styler uses HTML Parser to parse the content HTML. The parsed HTML is then styled.
For those curious what the plugin does in the back-end of things, here are three files that will give you a good idea of what the plugin does to your content. Please note that Feed Styler does not permanently modify your content.
The Sample Code is the type of code you might find in a regular blog post: headings, paragraphs, blockquotes, lists, etc… The plugin determines if the content being served to the user is a feed. If the content is a feed, the content is run through the Feed Styler filter. All IDs, Classes, and Tags that have styles specified in Feed Styler will have the appropriate inline style added. Any feed reader that doesn’t strip out inline styles (shame on you FeedDemon) will now show a styled feed.
Not all feed readers support inline styles. For example, FeedDemon doesn’t support inline styles. So don’t fully rely on Feed Styler for the appearance of your feed.
Here are some more tips: