- From: Alan Gresley <alan@css-class.com>
- Date: Thu, 26 Jun 2014 00:31:35 +1000
- To: Rik Cabanier <cabanier@gmail.com>
- CC: www-style list <www-style@w3.org>, "public-fx@w3.org" <public-fx@w3.org>
On 25/06/2014 11:53 PM, Alan Gresley wrote: > On 21/06/2014 2:42 AM, Rik Cabanier wrote: >> On Thu, Jun 19, 2014 at 11:29 PM, Alan Gresley <alan@css-class.com> >> wrote: >> >>> On 20/06/2014 12:40 PM, Rik Cabanier wrote: [snip] >>>> All browsers implement painting of the root backdrop by drawing the >>>> background color and images on top of a 100% opaque white backdrop. >>>> >>> >>> This is not quite true. In the Firefox setting for 'Content > >>> Colors', IE >>> setting 'Appearance > Colors' and Opera setting for 'Preferences > >>> Webpages', I can change the background/backdrop of the root element >>> to at >>> least a minimum of 70 colors. Internally, each UA has a hidden element >>> wrapping the root element. For old Opera (not sure about Blink), this >>> was a >>> black backdrop. >> >> >> This is unspecified behavior. Below is the specified behavior. It's what puts the *C* (cascading) into CSS. http://www.w3.org/TR/CSS21/conform.html#style-sheet | Style sheets may have three different origins: | author, user, and user agent. The interaction | of these sources is described in the section | on cascading and inheritance. If we follow the link for cascading and inheritance, we can find a note below section 6.4. http://www.w3.org/TR/CSS21/cascade.html#cascade | Note that the user may modify system settings | (e.g., system colors) that affect the default | style sheet. However, some user agent | implementations make it impossible to change | the values in the default style sheet. The last part of section 6.4.1 has the following (this part of the spec is not followed by Chrome): | Apart from the "!important" setting on | individual declarations, this strategy gives | author's style sheets higher weight than those | of the reader. User agents must give the user | the ability to turn off the influence of | specific author style sheets, e.g., through | a pull-down menu. Conformance to UAAG 1.0 | checkpoint 4.14 satisfies this condition [UAAG10]. If we follow the link for UAAG10, we arrive at the spec for 'User Agent Accessibility Guidelines 1.0' and checkpoint 4.14 is found here. http://www.w3.org/TR/2002/REC-UAAG10-20021217/guidelines.html#gl-user-control-styles -- Alan Gresley http://css-3d.org/ http://css-class.com/
Received on Wednesday, 25 June 2014 14:32:05 UTC