Remove invalid references to margin-box (#28157)

* Remove references to margin-box

margin-box was removed in the 2021 5 August 2021 Candidate Reccomendation, see https://drafts.fxtf.org/css-masking-1/#changes

* Remove margin-box from mask-clip

* Replace Geometry box with Coord box

Geometry box is from an old spec, and has since been replaced with Coord box. Additionally only some of the possible values were listed, now all of them are

* Remove dash in margin box to match W3 spec

In https://drafts.csswg.org/css-box-4/#margin-edge the area of the margin edges is described as the margin box, without a dash. margin-box is used elsewhere in https://drafts.csswg.org/css-box-4/#keywords as a keyword for some box edges. I think the use of it on this page is much more similar to the first example so probably shouldn't use a dash.

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Co-authored-by: Chris Mills <[email protected]>

files/en-us/web/css/css_box_model/introduction_to_the_css_box_model/index.md

@@ -32,7 +32,7 @@ The thickness of the borders are determined by the {{cssxref("border-width")}} a
 
 ## Margin area
 
-The **margin area**, bounded by the margin edge, extends the border area to include an empty area used to separate the element from its neighbors. Its dimensions are the _margin-box width_ and the _margin-box height_.
+The **margin area**, bounded by the margin edge, extends the border area to include an empty area used to separate the element from its neighbors. Its dimensions are the _margin box width_ and the _margin box height_.
 
 The size of the margin area is determined by the {{cssxref("margin-top")}}, {{cssxref("margin-right")}}, {{cssxref("margin-bottom")}}, {{cssxref("margin-left")}}, and shorthand {{cssxref("margin")}} properties. When [margin collapsing](/en-US/docs/Web/CSS/CSS_box_model/Mastering_margin_collapsing) occurs, the margin area is not clearly defined since margins are shared between boxes.
 

files/en-us/web/css/mask-clip/index.md

@@ -16,7 +16,6 @@ The **`mask-clip`** [CSS](/en-US/docs/Web/CSS) property determines the area whic
 mask-clip: content-box;
 mask-clip: padding-box;
 mask-clip: border-box;
-mask-clip: margin-box;
 mask-clip: fill-box;
 mask-clip: stroke-box;
 mask-clip: view-box;
@@ -52,8 +51,6 @@ One or more of the keyword values listed below, separated by commas.
   - : The painted content is clipped to the padding box.
 - `border-box`
   - : The painted content is clipped to the border box.
-- `margin-box`
-  - : The painted content is clipped to the margin box.
 - `fill-box`
   - : The painted content is clipped to the object bounding box.
 - `stroke-box`

files/en-us/web/css/mask-origin/index.md

@@ -18,7 +18,6 @@ For elements rendered as a single box, this property specifies the mask position
 mask-origin: content-box;
 mask-origin: padding-box;
 mask-origin: border-box;
-mask-origin: margin-box;
 mask-origin: fill-box;
 mask-origin: stroke-box;
 mask-origin: view-box;
@@ -50,8 +49,6 @@ One or more of the keyword values listed below, separated by commas.
   - : The position is relative to the padding box. For single boxes `0 0` is the upper left corner of the padding edge, `100% 100%` is the lower right corner.
 - `border-box`
   - : The position is relative to the border box.
-- `margin-box`
-  - : The position is relative to the margin box.
 - `fill-box` {{Experimental_Inline}}
   - : The position is relative to the object bounding box.
 - `stroke-box` {{Experimental_Inline}}

files/en-us/web/css/offset-path/index.md

@@ -30,9 +30,13 @@ offset-path: inset(50% 50% 50% 50%);
 offset-path: polygon(30% 0%, 70% 0%, 100% 50%, 30% 100%, 0% 70%, 0% 30%);
 offset-path: path("M 0,200 Q 200,200 260,80 Q 290,20 400,0 Q 300,100 400,200");
 
-/* Geometry box */
-offset-path: margin-box;
+/* Coord box */
+offset-path: content-box;
+offset-path: padding-box;
+offset-path: border-box;
+offset-path: fill-box;
 offset-path: stroke-box;
+offset-path: view-box;
 
 /* Global values */
 offset-path: inherit;