[css-align] Move statement about spanning into details section, to avoid confusion. #1037

Author: fantasai

css-align/Overview.bs

@@ -803,7 +803,7 @@ Baseline Content-Alignment</h3>
 		<dt>Table Cells:
 		<dd>
 			A <a>table cell</a> participates in first (last) <a>baseline content-alignment</a>
-			in either its row or column (whichever matches its <a>inline axis</a>)
+			in its startmost (endmost) row or column (whichever matches its <a>inline axis</a>)
 			if its computed 'align-content' is ''first baseline'' (''last baseline'').
 
 		<dt>Flex Items:
@@ -821,7 +821,7 @@ Baseline Content-Alignment</h3>
 		<dt>Grid Items:
 		<dd>
 			A <a>grid item</a> participates in first (last) <a>baseline content-alignment</a>
-			in either its row or column (whichever matches its <a>inline axis</a>)
+			in its startmost (endmost) row or column (whichever matches its <a>inline axis</a>)
 			if its computed 'align-content' is ''first baseline'' (''last baseline''),
 			and its computed 'align-self' or 'justify-self' (whichever affects its <a>block axis</a>)
 			is ''align-self/stretch'' or ''self-start'' (''self-end'').
@@ -831,10 +831,6 @@ Baseline Content-Alignment</h3>
 			whichever they end up equivalent to.
 	</dl>
 
-	If a box spans multiple <a>shared alignment contexts</a>,
-	it participates in first (last) <a>baseline content-alignment</a>
-	within its start-most (end-most) <a>shared alignment context</a> along that axis.
-
 	When a box participates in first (last)
 	<dfn export lt="baseline content-alignment|first-baseline content-alignment|last-baseline content-alignment">baseline content-alignment</dfn>
 	it effectively aligns its start (end) edge
@@ -1347,15 +1343,11 @@ Baseline Self-Alignment</h3>
 		<dt>Grid Items:
 		<dd>
 			A <a>grid item</a> participates in first (last) <a>baseline self-alignment</a>
-			in its row or column
+			in its startmost (endmost) row or column
 			if its 'align-self' or 'justify-self' property (respectively)
 			computes to ''first baseline'' (''last baseline'').
 	</dl>
 
-	If a box spans multiple <a>shared alignment contexts</a>,
-	it participates in first (last) <a>baseline self-alignment</a>
-	within its start-most (end-most) <a>shared alignment context</a> along that axis.
-
 	When a box participates in first (last)
 	<dfn export lt="baseline self-alignment|first-baseline self-alignment|last-baseline self-alignment">baseline self-alignment</dfn>
 	it effectively first aligns its start (end) edge
@@ -1614,7 +1606,7 @@ Baseline Alignment Terminology</h3>
 	Boxes share an <dfn lt="shared alignment context|alignment context" export>alignment context</dfn>,
 	along a particular axis,
 	and established by a particular box,
-	.when they are:
+	when they are:
 
 	<ul>
 		<li>table cells in the same row, along the table's row (inline) axis, established by the row box
@@ -1631,6 +1623,15 @@ Baseline Alignment Terminology</h3>
 	not any of the properties defined in this module.
 	See [[CSS-INLINE-3]].
 
+	If a box spans multiple <a>shared alignment contexts</a>,
+	then it participates in first (last) baseline alignment
+	within its start-most (end-most) <a>shared alignment context</a> along that axis.
+	For example, a table cell spanning three rows
+	participates in <a>first-baseline alignment</a>
+	with the table cells in the first row that it spans,
+	or alternatively in <a>last-baseline alignment</a>
+	with the table cells in the last row that it spans.
+
 	The <a>baseline alignment preferences</a> of two boxes in a <a>baseline-sharing group</a> are compatible if they have:
 
 	* the same <a>block flow direction</a> and <a>baseline alignment preference</a>