Web applications are taking the place of desktop apps and the same is happening to our development tools as well.
Developers like to edit their web applications with web based online tools rather than being offline with desktop applications. However such web-based code editors perform bit slow while comparing with desktop tools and applications. But nowadays such applications are focusing on providing a similar or better experience with desktop based ones.
Brackets, although being web-based, works in a native shell (Win & Mac versions available) to reach the file system.
BluePen Editor is a PHP-powered CSS editor that can be installed to any static or dynamic website and makes live CSS editing possible. Once triggered (with a bookmarklet), it opens the editor widget and makes all HTML elements hoverable so that blupePen can locate the CSS rules of them (like Chrome Dev Tools).
The editor used is the simple + functional AceEditor and there are multiple options for each beautifier to get the best results.