Top Style Lite, Best Completely Free Editor for CSS

Cascading Style Sheets (CSS) is a style sheet language that used to describe the presentation (that is, the look and formatting) of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can be applied to any kind of XML document, including SVG and XUL.

There is a simple editor of CSS, it's Top Style Lite. It use tree style to display the parts of a CSS file, like Explorer Style.
There are some excess that you can feel. The first, top style lite can preview the CSS that opened.
Second, it has Style Inspector that can inspect the contents of CSS and style for most of web browser like Firefox, IE, and the others, CSS for mobile included.Third, its size is small enough (only 1.4...Megabytes).

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