Nearly all browsers nowadays support CSS and many other applications do, too. To write CSS, you don't need more than a text editor, but there are many tools available that make it even easier.
Of course, nearly all software has bugs. And some programs are further ahead implementing the latest CSS modules than others. Various sites describe bugs and work-arounds.
Links to official feature lists of various products.
Several people maintain independent CSS support charts:
These sources document the level of support in various browsers:
Currently, most Web authoring tools provide some sort of support for CSS style sheets. The list below is far from complete, but contains (in chronological order) all tools that have been reported to us.
YesLogic has released Prince 7.1, a program to
produce PDF from HTML, MathML, SVG and generic XML. This version
adds PDF actions and some experimental features, such as Web Fonts in WOFF, a 'table-baseline'
property (especially useful for math), and a 'border-clip'
property (to suppress parts of a border). Prince offers many
(standard or proposed) CSS3 features, including hyphenation,
rounded corners and footnotes. (Windows, Mac OS X, Solaris, Linux
(i386), BSD; free personal license)
Version 3 of the
Sass preprocessor for CSS adds
a new input syntax that is a pure superset of CSS. This makes it
easy to use Sass with existing style sheets. The Python-style
indented syntax is also still available. Can be used stand-alone
or integrated in Ruby-on-Rails (Ruby, Open Source)
