[css-align] Define the writing mode fo the alignment subject/container for the *-self properties.

Author: tabatkins

css-align/Overview.bs

@@ -988,14 +988,15 @@ Inline/Main-Axis Alignment: the 'justify-self' property</h3>
 		<tr>
 			<th>'justify-self' Axis
 			<td>
-				The block’s containing block’s <a>inline axis</a>.
+				The block’s <a>containing block’s</a> <a>inline axis</a>.
 		<tr>
 			<th><a>Alignment Container</a>
 			<td>
-				The block's containing block,
-				except that for block-level elements that establish a block formatting context
+				The block's <a>containing block</a>,
+				except that for block-level elements that establish a <a>block formatting context</a>
 				and are placed next to a float,
-				the <a>alignment container</a> is reduced by the space taken up by the float.
+				the <a>alignment container</a> is reduced by the space taken up by the float,
+				assuming the <a>writing mode</a> of the <a>containing block</a>.
 
 				Issue: This is the legacy behavior of HTML <code>align</code>.
 				Do we want to still do this,
@@ -1005,7 +1006,8 @@ Inline/Main-Axis Alignment: the 'justify-self' property</h3>
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
-				The block's margin box.
+				The block's margin box,
+				assuming the <a>writing mode</a> of the block.
 		<tr>
 			<th>''justify-self/normal'' Behavior
 			<td>
@@ -1040,12 +1042,14 @@ Inline/Main-Axis Alignment: the 'justify-self' property</h3>
 		<tr>
 			<th><a>Alignment Container</a>
 			<td>
-				The box's containing block,
-				as modified by the inset properties ('top'/'right'/'bottom'/'left').
+				The box's <a>containing block</a>,
+				as modified by the inset properties ('top'/'right'/'bottom'/'left'),
+				assuming the <a>writing mode</a> of the <a>containing block</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
-				The box's margin box.
+				The box's margin box,
+				assuming the <a>writing mode</a> of the <a>box</a>.
 		<tr>
 			<th>''justify-self/normal'' Behavior
 			<td>
@@ -1093,12 +1097,14 @@ Inline/Main-Axis Alignment: the 'justify-self' property</h3>
 			<th><a>Alignment Container</a>
 			<td>
 				The box's <a>static-position rectangle</a>,
-				as defined by its parent box's layout mode.
+				as defined by its parent box's layout mode,
+				assuming the <a>writing mode</a> of the <a href="https://www.w3.org/TR/CSS2/visudet.html#static-position">static-position containing block</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
 				The box's margin box <em>after</em> laying out the box,
-				treated as fixed-size for the purpose of alignment.
+				treated as fixed-size for the purpose of alignment,
+				assuming the <a>writing mode</a> of the box.
 		<tr>
 			<th>''justify-self/normal'' Behavior
 			<td>
@@ -1127,11 +1133,13 @@ Inline/Main-Axis Alignment: the 'justify-self' property</h3>
 		<tr>
 			<th><a>Alignment Container</a>
 			<td>
-				The <a>grid item’s</a> <a>grid area</a>.
+				The <a>grid item’s</a> <a>grid area</a>,
+				assuming the <a>writing mode</a> of the <a>grid container</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
-				The <a>grid item’s</a> margin box.
+				The <a>grid item’s</a> margin box,
+				assuming the <a>writing mode</a> of the <a>grid item</a>.
 		<tr>
 			<th>''justify-self/normal'' Behavior
 			<td>
@@ -1210,16 +1218,18 @@ Block/Cross-Axis Alignment: the 'align-self' property</h3>
 		<tr>
 			<th>'align-self' Axis
 			<td>
-				The box’s containing block’s <a>block axis</a>.
+				The box’s <a>containing block’s</a> <a>block axis</a>.
 		<tr>
 			<th><a>Alignment Container</a>
 			<td>
-				The box's containing block,
-				as modified by the inset properties.
+				The box's <a>containing block</a>,
+				as modified by the inset properties,
+				assuming the <a>writing mode</a> of the <a>containing block</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
-				The box’s margin box.
+				The box’s margin box,
+				assuming the <a>writing mode</a> of the box.
 		<tr>
 			<th>''align-self/normal'' Behavior
 			<td>
@@ -1267,12 +1277,14 @@ Block/Cross-Axis Alignment: the 'align-self' property</h3>
 			<th><a>Alignment Container</a>
 			<td>
 				The box's <a>static-position rectangle</a>,
-				as defined by its parent box's layout mode.
+				as defined by its parent box's layout mode,
+				assuming the <a>writing mode</a> of the <a href="https://www.w3.org/TR/CSS2/visudet.html#static-position">static-position containing block</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
 				The box's margin box <em>after</em> laying out the box,
-				treated as fixed-size for the purpose of alignment.
+				treated as fixed-size for the purpose of alignment,
+				assuming the <a>writing mode</a> of the box.
 		<tr>
 			<th>''align-self/normal'' Behavior
 			<td>
@@ -1295,11 +1307,13 @@ Block/Cross-Axis Alignment: the 'align-self' property</h3>
 		<tr>
 			<th><a>Alignment Container</a>
 			<td>
-				The <a>flex line</a> the <a>flex item</a> is in.
+				The <a>flex line</a> the <a>flex item</a> is in,
+				assuming the <a>writing mode</a> of the <a>flex container</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
-				The <a>flex item’s</a> margin box.
+				The <a>flex item’s</a> margin box,
+				assuming the <a>writing mode</a> of the <a>flex item</a>.
 		<tr>
 			<th>''align-self/normal'' Behavior
 			<td>
@@ -1318,11 +1332,13 @@ Block/Cross-Axis Alignment: the 'align-self' property</h3>
 		<tr>
 			<th><a>Alignment Container</a>
 			<td>
-				The [=grid item’s=] <a>grid area</a>.
+				The [=grid item’s=] <a>grid area</a>,
+				assuming the <a>writing mode</a> of the <a>grid container</a>.
 		<tr>
 			<th><a>Alignment Subject</a>
 			<td>
-				The <a>grid item’s</a> margin box.
+				The <a>grid item’s</a> margin box,
+				assuming the <a>writing mode</a> of the <a>grid item</a>.
 		<tr>
 			<th>''align-self/normal'' Behavior
 			<td>