From Wikipedia, the free encyclopedia

The following tables compare CSS compatibility and support for a number of layout engines. Please see the individual products' articles for further information. This article is not all-inclusive or necessarily up-to-date. Unless otherwise specified in footnotes, comparisons are based on the stable versions without any add-ons, extensions or external programs.

Rather than the names of web browsers, the names of the underlying engines are used. The browsers that use the various engines are listed below.

• Trident – Internet Explorer. IE6 uses Trident IV; IE7 uses Trident V.
• Tasman – Internet Explorer 5 for Apple Mac.
• Gecko – Various open-source browsers (Firefox, Netscape 6+, Camino, Flock, SeaMonkey, K-Meleon)
• WebCore – Apple Safari
• KHTML – Konqueror. KHTML and WebCore are quite similar, and developments in one are often copied to the other.
• Presto – Opera 7+
• iCab – iCab

Values indicate the level of support in the most recent version of the layout engine, or (if a version number is given) in the specified version. Version numbers without any other value indicate the version at which the layout engine first fully supported the feature.

Value	Meaning
Yes	Indicates that the layout engine fully supports this property when valid values are used.
No	Indicates that this property is completely ignored.
Partial	Indicates that the property is understood, but that not all values are supported. Supported values are implemented correctly.
Buggy	Indicates that the property is understood, but that it is not implemented correctly in all cases.
Experimental	Indicates that the property is provided in experimental form under an alternative name, generally with only partial functionality.

This article or section is incomplete and may require expansion and/or cleanup. Please improve the article, or discuss the issue on the talk page.

See the article Cascading Style Sheets for more information on the different versions of CSS. This table doesn't reference CSS2.0, as CSS2.1 was intended to replace it by correcting or removing a few errors and features rejected by the CSS community. Most of the removed CSS2 features will be made obsolete by CSS3.

	Trident	Tasman	Gecko	WebCore	KHTML	Presto	iCab
CSS1	6.0	0	1.0	85	Yes	7.0	Yes
CSS2.1	Partial	Partial	Mostly	Mostly	Mostly	Mostly	Mostly
CSS3	No	No	Slight	Slight	Slight	Partial	Slight

			Trident	Tasman	Gecko	WebCore	KHTML	Presto	iCab
CSS2	important	Weight increasing	7.0	0	1.0	85	Yes	7.0	Yes
	/*Comment*/	Comments	3.0	0	1.0	85	Yes	7.0	Yes
	@import	Import stylesheet	4.0	0	1.0	Yes	Yes	7.0	Yes
	@charset	Character set	5.5	?	1.0	0	No	7.0	Yes
	@media	Media-specific rules	5.5	0.9	1.0	Yes	Yes	7.0	3.0
	@page	For paged media	5.5	No	No	No	No	7.0	No
CSS3	@namespace	Namespace declaration	No	No	1.0	Yes	Yes	8.0	No
	@font-face	Define font	5.5	No	No	r26067 [1]	No	No	No

1. @font-face — Only supports Embedded OpenType (.eot) font format, does not understand the format() identifier.
2. !important — !important doesn't override rules defined later in the same declaration block prior to IE7.

1. @font-face — Versions 5.16 and 5.17 will download fonts specified but not use them. 5.23 no longer downloads the font.

1. @import — Whilst Gecko, WebCore and iCab download all media stylesheets immediately, Opera only downloads handheld, print, projection and screen media, as well as speech if "voice" feature is enabled and tv, on tv devices. Text browser emulation mode is only a user stylesheet, so it does not switch to tty media type. This is consistent with older text browsers, which do not respect any CSS.

			Trident	Tasman	Gecko	WebCore	KHTML	Presto	iCab
Element selectors
CSS2	*	Universal	7.0	0	1.0	85	Yes	7.0	3.0
	E	Element	4.0	0	1.0	85	Yes	7.0	Yes
	E.class	Class	7.0	Buggy	1.0	85	Yes	7.0	Yes
	E#id	ID	4.0	0	1.0	85	Yes	7.0	Yes
CSS3	ns|E	Namespaced	No	No	1.0	No	Yes	8.0	No
Relationship selectors
CSS2	E F	Descendant	4.0	0	1.0	85	Yes	7.0	Yes
	E > F	Child	7.0	0	1.0	85	Yes	7.0	3.0
	E + F	Direct adjacent	7.0	0	1.0	85	Yes	7.0	3.0
CSS3	E ~ F	Indirect adjacent	7.0	0.9	1.7	412	3.3.2	9.0	3.0
Attribute selectors
CSS2	E[attr]	Has	7.0	0.9	1.0	85	Yes	7.0	3.0
	E[attr="value"]	Equals	7.0	0.9	1.0	Yes	Yes	7.0	3.0
	E[attr~="value"]	Contains (space-separated)	7.0	0.9	1.0	Yes	Yes	7.0	3.0
	E[attr|="value"]	Contains (hyphen-separated)	7.0	0.9	1.0	Yes	Yes	7.0	3.0
CSS3	E[attr^="value"]	Begins with	7.0	No	1.0	Yes	3.4	8.02	3.0
	E[attr$="value"]	Ends with	7.0	No	1.0	Yes	3.4	9.0	3.0
	E[attr*="value"]	Contains substring	7.0	No	1.0	Yes	3.4	9.0	3.0
	E[ns|attr]	Namespaced	No	No	1.0	No	3.4	9.0	No
Pseudo-classes
CSS2	E:link	Unvisited hyperlink	3.0	0	1.0	85	Yes	7.0	Yes
	E:visited	Visited hyperlink	3.0	0	1.0	85	Yes	7.0	Yes
	E:active	Active	Partial	0	1.0	85	Yes	7.0	Yes
	E:hover	Mouseover	7.0	0.9	1.0	419.3	Yes	7.0	3.0
	E:focus	Focused	No	0	1.0	Yes	Yes	7.0	Yes
	E:first-child	First child	7.0	0	1.0	85	Yes	7.0	3.0
	E:lang()	Language	No	0	1.2	522	3.4	7.5	3.0
CSS3	E:root	Root	No	0.1	1.0	85	3.4	9.5a	No
	E:first-of-type	First child of type	No	0.9	No	522	3.4	9.5a	No
	E:last-child	Last child	No	0.9	1.0	Buggy	3.4	9.5a	No
	E:last-of-type	Last child of type	No	0.9	No	Buggy	3.4	9.5a	No
	E:only-child	Only child	No	0.9	1.8	Buggy	3.4	9.5a	No
	E:only-of-type	Only child of type	No	0.9	No	Buggy	3.4	9.5a	No
	E:nth-child	Nth child	No	0.9	No	No	3.4	9.5a	No
	E:nth-last-child	Nth last child	No	0.9	No	No	3.4	9.5a	No
	E:nth-of-type	Nth child of type	No	0.9	No	No	3.4	9.5a	No
	E:nth-last-of-type	Nth last child of type	No	0.9	No	No	3.4	9.5a	No
	E:target	Target	No	0.9	1.3	Partial	3.4	9.5a	No
	E:empty	Empty	No	0.9	1.8	412	3.4	9.5a	No
	E:not()	Negation	No	0.9	1.0	85	3.4	9.5a	No
	E:enabled	Enabled state	No	0.9	1.8	522	3.4	9.0	No
	E:disabled	Disabled state	No	0.9	1.8	522	3.4	9.0	No
	E:checked	Checked state	No	No	1.0	522	3.4	9.0	No
	E:indeterminate	Indeterminate state	No	0.9	No	No	No	No	No
	E:default	Default	No	No	1.9	No	No	9.0	No
	E:valid	Valid	No	No	1.8	No	No	9.0	No
	E:invalid	Invalid	No	No	1.8	No	No	9.0	No
	E:in-range	In range	No	No	1.8	No	No	9.0	No
	E:out-of-range	Out of range	No	No	1.8	No	No	9.0	No
	E:required	Required	No	No	No	No	No	9.0	No
	E:optional	Optional	No	No	No	No	No	9.0	No
	E:read-only	Read-only	No	No	Experimental	No	No	9.0	No
	E:read-write	Read and write	No	No	Experimental	No	No	9.0	No
Pseudo-elements
CSS2	E:first-letter	First letter	5.5	0	1.0	85	Yes	7.0	3.0
	E:first-line	First line	5.5	0	1.0	85	Yes	7.0	3.0
	E:before	Before	No	No	1.0	85	Yes	7.0	3.0
	E:after	After	No	No	1.0	85	Yes	7.0	3.0
CSS3	E::before	Double colon notation	No	No	1.5	85	3.4	7.0	Yes
	E::after	Double colon notation	No	No	1.5	85	3.4	7.0	Yes
	E::first-letter	Double colon notation	No	0.9	1.5	85	3.4	7.0	Yes
	E::first-line	Double colon notation	No	0.9	1.5	85	3.4	7.0	Yes
	E::selection	Selection	No	0.9	Experimental	412	3.4	No	No
	E::value	Double colon notation	No	No	No	No	No	No	No
	E::choices	Double colon notation	No	No	No	No	No	No	No
	E::repeat-item	Double colon notation	No	No	No	No	No	No	No
	E::repeat-index	Double colon notation	No	No	No	No	No	No	No
			Trident	Tasman	Gecko	WebCore	KHTML	Presto	iCab

1. :active — :active is for anchor element only.
2. :hover — :hover is applied for all elements only in standards-compliant mode, not quirks mode [2]. Prior to 7.0, :hover is for anchor element only.
3. .one.two — only .two class selector was taken into consideration before 7.0.
4. * — Prior to 7.0 this was treated as a single or no element.

1. :hover — For anchor element only prior to 0.9.
2. .one.two — only .two class selector is taken into consideration.

1. :lang() — Only detected when explicitly present on element being tested, attribute not inherited.
2. :target — Style doesn't get applied when navigating using back and forward buttons.
3. :last-child & :last-of-type — will match all siblings, or all siblings of the same type, respectively.
4. :only-child & :only-of-type — identical behaviour to :first-child & :first-of-type.
5. ::pseudo-element — Mistakenly also triggers on ::pseudo-class prior to version 416.0.

		Trident	Tasman	Gecko	WebCore	KHTML	Presto	iCab
Box model
CSS2	margin	4.0	0	1.0	85	Yes	7.0	3.0
	padding	4.0	0	1.0	85	Yes	7.0	3.0
	width	4.0	0	1.0	85	Yes	7.0	3.0
	height	4.0	0	1.0	85	Yes	7.0	3.0
	float	5.0	0	1.0	85	Yes	7.0	3.0
	clear	5.0	0	1.0	85	Yes	7.0	Yes
	display	Partial	Partial	Partial	85	Yes	7.0	Partial
	min-width	7.0	0.9	1.0	416	Yes	7.0	3.0
	max-width	7.0	0.9	1.0	416	Yes	7.0	3.0
	min-height	7.0	0.9	1.7	416	3.3.2	7.0	3.0
	max-height	7.0	0.9	1.7	416	3.3.2	7.0	3.0
	clip	5.5	0.9	1.0	85	Yes	7.0	3.0
	overflow	7.0	0	1.0	85	3.2	7.0	3.0
	visibility	4.0	0.9	1.8	522	Partial	Partial	Partial
CSS3	overflow-x	7.0	No	1.8	522	3.5.6	9.5a	No
	overflow-y	7.0	No	1.8	522	3.5.6	9.5a	No
Borders
CSS2	border	4.0	0	1.0	85	Yes	7.0	3.0
	border-color	4.0	0	1.0	85	Yes	7.0	3.0
	border-style	7.0	0	1.0	85	Yes	7.0	3.0
	border-width	4.0	0	1.0	85	Yes	7.0	3.0
	border-top	5.5	0	1.0	85	Yes	7.0	3.0
	border-top-width	5.5	0	1.0	85	Yes	7.0	3.0
	border-right	5.5	0	1.0	85	Yes	7.0	3.0
	border-right-width	5.5	0	1.0	85	Yes	7.0	3.0
	border-bottom	5.5	0	1.0	85	Yes	7.0	3.0
	border-bottom-width	5.5	0	1.0	85	Yes	7.0	3.0
	border-left	5.5	0	1.0	85	Yes	7.0	3.0
	border-left-width	5.5	0	1.0	85	Yes	7.0	3.0
	border-top-color	4.0	0	1.0	85	Yes	7.0	3.0
	border-top-style	5.5	0	1.0	85	Yes	7.0	3.0
	border-right-color	4.0	0	1.0	85	Yes	7.0	3.0
	border-right-style	5.5	0	1.0	85	Yes	7.0	3.0
	border-bottom-color	4.0	0	1.0	85	Yes	7.0	3.0
	border-bottom-style	5.5	0	1.0	85	Yes	7.0	3.0
	border-left-color	4.0	0	1.0	85	Yes	7.0	3.0
	border-left-style	5.5	0	1.0	85	Yes	7.0	3.0
CSS3	border-radius	No	No	Experimental	Experimental	Experimental	No	No
	border-break	No	No	No	No	No	No	No
	border-image	No	No	No	Experimental	No	No	No
	box-shadow	No	No	No	Experimental	No	No	No
Line Layout
CSS2	line-height	4.0	0	1.0	85	Yes	7.0	Yes
	vertical-align	5.5	0	1.0	85	Yes	7.0	3.0
Positioning
CSS2	position	7.0	0	1.0	85	Yes	7.0	3.0
	top	Partial	Partial	1.0	85	Yes	7.0	3.0
	right	Partial	Partial	1.0	85	Yes	7.0	3.0
	bottom	Partial	Partial	1.0	85	Yes	7.0	3.0
	left	Partial	Partial	1.0	85	Yes	7.0	3.0
	z-index	Partial	Partial	1.0	85	Yes	7.0	3.0
Generated and Replaced Content
CSS2	quotes	No	0.9	1.8	No	3.4	7.0	3.0
	content		No	Partial	85	Yes	7.0	3.0
	counter-increment		No	1.8	522	3.4	7.0	3.0
	counter-reset		No	1.8	522	3.4	7.0	3.0
Lists
CSS2	list-style	4.0	0	1.0	85	Yes	7.0	3.0
	list-style-image	4.0	0	1.0	85	Yes	7.0	3.0
	list-style-position	4.0	0	1.0	85	Yes	7.0	3.0
	list-style-type	Partial	0	1.0	85	3.4	8.0	3.0
Colors
CSS2	color	3.0	0	1.0	85	Yes	7.0	Yes
CSS3	color-profile	No	No	No	No	No	No	No
	opacity	Non-Standard	No	1.7	125	Experimental	9.0	No
	rendering-intent	No	No	No	No	No	No	No
Backgrounds
CSS2	background	4.0	0	1.0	85	Yes	7.0	Yes
	background-attachment	7.0	0	1.0	85	Yes	7.0	Yes
	background-color	4.0	0	1.0	85	Yes	7.0	3.0
	background-image	4.0	0	1.0	85	Yes	7.0	Yes
	background-position	Partial	0	1.0	85	Yes	7.0	Yes
	background-repeat	4.0	0	1.0	85	Yes	7.0	Yes
CSS3	background (multiple)	No	No	No	312	3.5	No	No
	background-clip	No	No	Experimental	Experimental	Experimental	No	No
	background-origin	No	No	Experimental	Experimental	Experimental	No	No
	background-break	No	No	No	No	No	No	No
	background-size	No	No	No	Experimental	Experimental	9.5	No
Fonts
CSS2	font	4.0	0	1.0	85	Yes	7.0	Yes
	font-family	4.0	0	1.0	85	Yes	7.0	Yes
	font-size	3.0	0	1.0	85	Yes	7.0	Yes
	font-style	4.0	0	1.0	85	Yes	7.0	Yes
	font-variant	4.0	0	1.0	125	Yes	7.0	3.0
	font-weight	Buggy	0	Partial	Partial	Yes	Buggy	Buggy
CSS3	font-size-adjust	No	No	Partial	No	No	No	No
	font-stretch	No	No	No	No	No	No	Buggy
	font-effect	No	No	No	No	No	No	No
	font-smooth	No	No	No	No	No	No	No
	font-emphasize	No	No	No	No	No	No	No
Text
CSS2	text-align	4.0	0	1.0	85	Yes	7.0	Partial
	text-decoration	4.0	0	1.0	85	Yes	7.0	3.0
	text-indent	3.0	0	1.0	85	Yes	7.0	Yes
	text-transform	4.0	0	1.0	85	Yes	7.0	Yes
	letter-spacing	4.0	0	1.0	85	Yes	7.0	Yes
	word-spacing	Partial	Partial	1.0	85	Yes	7.0	Yes
	white-space	Partial	Partial	Partial	85	Yes	Partial	Yes
	direction	5.0	0	1.0	85	Yes	7.2	No
	unicode-bidi	5.0	0	1.0	522	Yes	7.2	No
CSS3	text-shadow	No	No	No	Partial	3.4	9.5a	3.0.3
	text-overflow	Partial	No	No	Partial	No	Experimental	No
	word-break	Partial	No	No	No	No	No	No
	text-wrap	No	No	No	No	No	No	No
	word-wrap	5.0	No	No	85	No	No	No
	text-align-last	Partial	No	No	No	No	No	No
	text-justify	5.5	No	No	No	No	No	No
	punctuation-trim	No	No	No	No	No	No	No
	text-emphasis	No	No	No	No	No	No	No
	text-outline	No	No	No	No	No	No	No
	hanging-punctuation	No	No	No	No	No	No	No
Tables
CSS2	border-collapse	Partial	0.9	1.0	125	Yes	7.0	3.0
	border-spacing	No	0.9	1.0	125	Yes	7.0	3.0
	caption-side	No	0.9	1.4	85	Yes	7.0	CSS2.1
	empty-cells	Partial	0.9	1.0	125	Yes	7.0	Buggy
	table-layout	5.0	0	1.0	85	Yes	7.0	3.0
User interface
CSS2	cursor	5.5	0	1.8	125	Yes	7.0	3.0
	outline	No	0	1.8	125	Yes	7.0	3.0
	outline-color	No	0	1.8	125	Yes	7.0	3.0
	outline-style	No	0	1.8	125	Yes	7.0	3.0
	outline-width	No	0	1.8	125	Yes	7.0	3.0
CSS3	outline-offset	No	No	1.8	125	No	9.5a	No
	outline-radius	No	No	Experimental	No	No	No	No
	box-sizing	No	0	Experimental	522	3.3.2	7.0	No
	resize	No	No	No	522	No	No	No
	appearance	No	No	Experimental	Experimental	No	No	No
	icon	No	No	No	No	No	No	No
	nav-index	No	No	No	No	No	9.5	No
	nav-up	No	No	No	No	No	9.5	No
	nav-right	No	No	No	No	No	9.5	No
	nav-down	No	No	No	No	No	9.5	No
	nav-left	No	No	No	No	No	9.5	No
Paged media
CSS2	orphans	No	No	No	312	3.5	7.0	No
	page-break-after	4.0	No	Partial	Partial	3.5	7.0
	page-break-before	4.0	0	Partial	Partial	3.5	7.0
	page-break-inside	No	No	No	312	3.5	7.0
	widows	No	No	No	312	3.5	7.0
CSS3	page	No	No	No	No	No	No
	size	No	No	No	No	No	7.0
	image-orientation	No	No	No	No	No	No
	fit	No	No	No	No	No	No
	fit-position	No	No	No	No	No	No
Speech
CSS3	voice-volume	No	No	No	No	No	7.6	No
	voice-balance						7.6
	speak						7.6
	pause						7.6
	pause-after						7.6
	pause-before						7.6
	rest						No
	rest-before						No
	rest-after						No
	cue						7.6
	cue-after						7.6
	cue-before						7.6
	mark						No
	mark-before						No
	mark-after						No
	voice-family						7.6
	voice-rate						7.6
	voice-pitch						7.6
	voice-pitch-range						7.6
	voice-stress						7.6
	voice-duration						7.6
	phonemes						7.6
Media Queries
CSS3	width	No	No	No	522	No	9.0	No
	height				522		9.0
	device-width				522		9.0
	device-height				522		9.0
	device-aspect-ratio				522		9.0
	color				522		9.0
	color-index				522		9.0
	monochrome				522		9.0
	resolution				No		9.0
	scan				No		No
	grid				No		9.0
Ruby characters
CSS3	ruby-position	5.0	0	No	No	No	No	No
	ruby-align	5.0	0
	ruby-overhang	5.0	0
	ruby-span	No	No
Multi-column Layout
CSS3	column-break-before	No	No	Experimental	Experimental	No	No	No
	column-break-after			Experimental	Experimental
	column-break-inside			Experimental	Experimental
	column-count			Experimental	Experimental
	column-gap			Experimental	Experimental
	column-rule			No	No
	columns			Experimental	Experimental

1. overflow — overflow:visible is incorrectly supported prior to IE7.
2. border-style — dotted is rendered as dashed prior to IE7.
3. display — Only none, block, inline, table-header-group, and table-footer-group are supported prior to 7.0. In 5.5+, inline-block is supported on elements that are naturally inline.
4. position — Prior to IE 7, fixed positioning was not supported, IE 7 supports it in standards-compliant mode only.
5. background-attachment — Prior to IE 7, fixed was allowed on the body element only.
6. background-position — Fixed positioning is not supported.
7. font-weight — Incorrect rendering when value is 600 [3].
8. text-decoration — Optional property blink is not supported.
9. white-space — nowrap is supported in IE 5.5 and later. pre is supported in IE 6 and later in standards-compliant mode. pre-line and pre-wrap are not supported.
10. list-style-type — decimal-leading-zero, lower-greek, lower-latin, upper-latin, upper-roman are not supported.

1. display — run-in [4] is not supported. inline-table [5] and inline-block [6] are supported in Gecko 1.9a2+.
2. quotes — Does not support nested quotes prior to 1.8 [7].
3. content — Only works with :before and :after. Only support image . does not work prior to 1.8 [8].
4. background-position — Gecko versions prior to 1.7 implement the CSS2 syntax, not the proposed CSS2.1 expanded syntax.
5. font-size-adjust — Supported in Windows only[9]. This problem will be fixed in the future Gecko 1.9.
6. font-weight — Only Regular and Bold weights get used, even if Light or Heavy/Black faces are installed.
7. white-space — pre-line is not supported. pre-wrap is only supported experimentally as -moz-pre-wrap;.
8. visibility — collapse is not supported prior to 1.8.
9. border-radius — border curves are circular, but the W3C specs [10] define them as elliptical. Dashed curves are not available. Short-cut definitions for border-radius read "tl tr br bl" instead of the W3C's "tr br bl tl". Interesting bugs: [11] [12] [13]
10. page-break-before; page-break-after — Only the always and auto values are supported.

1. box-shadow — The system font keywords are not supported that allow designers to tailor presentation to the user’s operating system environment.
2. font — The system font keywords are not supported that allow designers to tailor presentation to the user’s operating system environment.
3. font-weight — Only Regular and Bold weights get used, even if Light or Heavy/Black faces are installed.
4. page-break-before; page-break-after — Only the always and auto values are supported.
5. text-decoration — Optional property blink is not supported.
6. white-space — pre-line and pre-wrap from the proposed CSS2.1 draft are not supported.
7. text-shadow — Multiple shadows are not supported.
8. visibility — collapse is not supported prior to 522.

1. overflow — Values scroll and auto are unsupported.
2. page-break-before; page-break-after — Before 3.5 only the always and auto values were supported.
3. text-decoration — Optional property blink is not supported.
4. visibility — All supported except for collapse.

1. list-style-type — The CSS2 values are not supported prior to 8.0.
2. counter-increment, counter-reset — Implemented the algorithm in REC CSS2.
3. background-position — Presto versions prior to 8.0 implement the CSS2 syntax, not the proposed CSS2.1 expanded syntax.
4. font-weight — Incorrect rendering when value is 600 [14].
5. white-space — pre-line is not supported prior to Opera 9.5.
6. visibility — collapse is unsupported until 9.5, in which collapse is only unsupported in table columns.

1. display — run-in is not supported.
2. text-align — justify is not supported.
3. font-stretch — Simulated using letter-spacing property.
4. font-weight — Incorrect (bold) rendering when value is 500.
5. visibility — collapse only partial.
6. caption-side — top and bottom only which would comply with the proposed CSS2.1 elimination of the values: left and right.
7. empty-cells — Compresses hidden rows but does not hide them completely.

				Trident	Tasman	Gecko	WebCore	KHTML	Presto	iCab
Numbers	CSS2		A floating-point number	3.0	0	1.0	85	Yes	7.0	Yes
			followed by units	3.0	0	1.0	85	Yes	7.0	Yes
			followed by %	3.0	0	1.0	Imprecise	Yes	7.0	Yes
			An integer	3.0	0	1.0	85	Yes	7.0	Yes
	CSS3		angle-unit	No	No	No	Yes	Yes	No	No
			time-unit				Yes	Yes
			frequency-unit				Yes	Yes
Strings	CSS2		String	3.0	0	1.0	85	Yes	7.0	Yes
		\code	Unicode escapes	6.0	0.9	1.0	85	Yes	7.0	Yes
Shapes	CSS2	rect()	A rectangle	5.5	0	1.0	85	Yes	7.0	Yes
Functions	CSS2	url()	Uniform Resource Identifier	3.0	0	1.0	85	Yes	7.0	Yes
		counter()		No	No	Yes	?	?	Yes	?
		attr()	Attribute identifier	No	No	1.0	Yes	Yes	7.0	Yes
	CSS3	calc()		No	No	?	?	?	?	?
Colors	CSS2	color names	16 predefined web colors	3.0	0	1.0	85	Yes	7.0	Yes
		#rrggbb or #rgb	Hexadecimal notation	3.0	0	1.0	85	Yes	7.0	Yes
		rgb(r,g,b)	RGB notation	4.0	0	1.0	85	Yes	7.0	Yes
		system colors	28 predefined system colors [15]	3.0	0	1.0	85	Yes	7.0	Yes
		transparent	Full transparency	7.0	0	1.0	85	Yes	7.0	Yes
	CSS3	rgba(r,g,b,a)	RGBA notation	No	No	1.9	522	Buggy	No	No
		hsl(h,s,l)	HSL notation	No	No	Yes	522	3.5.5	9.5	No
		hsla(h,s,l,a)	HSLA notation	No	No	1.9	522	3.5.5	No	No
Keywords	CSS2	auto	Automatically calculated	6.0	0	1.0	85	Yes	7.0	Yes
		inherit	Inherited from the parents	No	?	1.0	85	Yes	7.0	Yes
	CSS3	initial		No	No	Experimental	No	No	No	No
Units	CSS2	px	Pixel	3.0	0	1.0	85	Yes	7.0	Yes
		pt	Point	3.0	0	1.0	85	Yes	7.0	Yes
		pc	Pica	3.0	0	1.0	85	Yes	7.0	Yes
		cm	Centimetre	3.0	0	1.0	85	Yes	7.0	Yes
		mm	Millimetre	3.0	0	1.0	85	Yes	7.0	Yes
		in	inch	3.0	0	1.0	85	Yes	7.0	Yes
		em	em	3.0	0	1.0	85	Yes	7.0	Yes
		ex	ex	3.0	0	1.0	85	Yes	7.0	Yes
		%	Percentage	3.0	0	1.0	85	Yes	7.0	Yes
	CSS3	deg	Degree	No	No	No	Yes	Yes	No	No
		grad	Grad				Yes	Yes
		rad	Radian				Yes	Yes
		ms	Millisecond				Yes	Yes
		s	Second				Yes	Yes
		Hz	Hertz				Yes	Yes
		kHz	Kilohertz				Yes	Yes
		turn	turn				No	No
		gd	Cells in the layout-grid				No	No
		rem	the font size of the root element				No	No
		vw	the viewport's width				No	No
		vh	the viewport's height				No	No
		vm	the viewport's height or width, whichever is smaller of the two				No	No
		ch	The width of the "0" (ZERO, U+0030) glyph found in the font for the font size used to render.				No	No

1. auto — In IE5 bug emulation mode (quirks mode) does not work for margins, except table elements.
2. transparent — In IE6, transparency is not supported on borders (shows as solid black) and is ignored on PNG images. Thus, version 7.0 is the first version that supports transparency in its entirety.

1. — Only uses the integer component of .

1. attr() — As all URI attribute values are resolved to full URI, the value could be wrong if attr() is used on an attribute that contains relative URI.
2. — Quantization error for values greater than 20.47 [16] (not limited to em, try any non pixel units).

1. rgba() — Because opacity is not supported, the opacity value of rgba() is ignored.

1. -moz- — All experimental selectors, properties and values are prefixed with "-moz-", e.g. ::-moz-selection instead of ::selection [17].

1. -webkit- — All experimental selectors, properties and values are prefixed with "-webkit-", e.g. -webkit-box-shadow instead of box-shadow.

1. -khtml- — All experimental selectors, properties and values are prefixed with "-khtml-", e.g. -khtml-opacity instead of opacity.

1. -xv- — All new selectors, properties and values introduced by CSS3 Speech Module are prefixed with "-xv-" (but not found in CSS2 aural style sheets), e.g. -xv-voice-rate instead of voice-rate.

• W3C. CSS 1 test suite. Retrieved on May 1, 2005.
• W3C. CSS 2.1 test suite. Retrieved on May 1, 2005.
• mozilla.org Bugzilla. Bug 281960 - [devmo] Mozilla CSS support chart. Retrieved on July 13, 2005.
• Mozilla Developer Center. Mozilla CSS support chart. Retrieved on May 21, 2006.
• Opera Documentation. Web Specifications Supported in Opera - CSS. Retrieved on May 1, 2005.
• Internet & Web - Safari. CSS Support in Safari. Retrieved on July 13, 2005.
• Konqueror Homepage. CSS 2.1 & 3 Support in KHTML 3.4. Retrieved on July 13, 2005.
• Apple Developer Connection. Safari CSS Reference. Retrieved on July 14, 2005.

• WebDevout — mostly covers Windows browsers. Extensive bug testing.
• QuirksMode — comprehensive but lacks latest versions.
• Westciv — abridged form of their retail guide.
• MacEdition — covers many Mac browsers, including rare and discontinued ones.
• Jesset — simple table without bug details, includes WebTV.
• Motohiko — covers Firefox only. [Japanese]

• CSS Filters — a fairly complete table of browser-specific hacks
• CSS specification/browser support page: General Syntax
• Assigning external CSS

v • d • e Layout engines
List of layout engines	Trident · Presto · Gecko · Tasman · WebCore · KHTML · iCab · Prince · GtkHTML · Gzilla · Boxely · Tkhtml · Robin
Comparison of layout engines	HTML · XML · XHTML · Graphics · CSS · DOM · HTML 5 · ECMAScript · SVG