26588 2014-08-15 15:25:39 +0000 transform-origin: value definition and description are inconsistent 2015-08-20 04:23:50 +0000 1 1 1 Unclassified CSS Transforms unspecified PC All RESOLVED FIXED P2 normal --- 1 alexander.zolotov smfr ayg cmarrin dino dschulze eoconnor smfr public-css-bugzilla oldest_to_newest 110212 0 alexander.zolotov 2014-08-15 15:25:39 +0000 There is third part of value definition: [ center | [ left | right ] ] && [ center | [ top | bottom ] ] <length>? According to Css Values and Unit Module (http://dev.w3.org/csswg/css-values/#component-combinators) it should be interpreted as [ center | [ left | right ] ] && [ [ center | [ top | bottom ] ] <length>? ] Because 'Juxtaposition is stronger than the double ampersand'. It means that value 'left top 20cm' is valid. Since '&&' is re-orderable combinator the 'top 20cm left' value is valid too. But the description tells us that 'a third value always represents the Z position (or offset) and must be of type <length>' so 'top 20cm left' can't be valid. Please fix the description or add extra brackets in value definition like in following example: [ [ center | [ left | right ] ] && [ [ center | [ top | bottom ] ] ] <length>? Also it seems that brackets in '[left | right]' and '[top | bottom]' groups are redundant. 122682 1 smfr 2015-08-20 04:23:50 +0000 I changed it to: [ left | center | right | top | bottom | <percentage> | <length> ] | [ left | center | right | <percentage> | <length> ] [ top | center | bottom | <percentage> | <length> ] <length>? | [[ center | left | right ] && [ center | top | bottom ]] <length>? which I think is correct. I suspect it was copied from https://drafts.csswg.org/css-backgrounds-3/#position but without understanding the "edge plus delta" form that the final production is trying to address.