Compatibility

The selectors and properties below should all work according to the W3C specifications.

CSS2 Selectors (W3C)

Selector	Comments	Test
:active		html - xml
:focus		html
:hover		html - xml
:lang()		html
:first-child		html - xml
::after		html
::before		html
[attr]		html - xml
[attr="value"]		html - xml
[attr~="value"]		html - xml
[attr|="value"]		html - xml
parent > child		html - xml
adjacent + sibling		html - xml
.multiple.classes	IE5/6 bug fixed	html - xml

CSS3 Selectors (W3C)

Selector	Comments	Test
:empty		html - xml
:last-child		html - xml
:nth-child()		html
:nth-last-child()		html
:only-child		html
:root		html - xml
[attr^="value"]		html
[attr$="value"]		html
[attr*="value"]		html
adjacent ~ sibling		html - xml

CSS Properties

Property	Comments	Test
background-attachment	support fixed positioning	html
background-image	PNG alpha transparency	html - xml
box-sizing	content-box (assumed)	html
bottom	height implied if top is supplied	html
content		html
display	convert list-item to block for IE5
float	fix double margin bug	html
font-size	fix named font sizes (quirks mode)
min-width		html
min-height	implemented for IE5	html
max-width		html
max-height	can't do this one	:-(
position	support fixed positioning	html
right	width implied if left is supplied	html

HTML

Element	Comments	Test
abbr	IE5/6 bugs fixed	html
button[type=submit]	value submitted rather than innerText	html
form	only submit successful controls	html
img	PNG alpha transparency	html
label	bind to the first child control	html