[css-align-3][editorial] Fix headings #11333

Author: fantasai

css-align-3/Overview.bs

@@ -1357,7 +1357,7 @@ Self-Alignment: Aligning the Box Within Its Parent</h2>
 	</div>
 
 <h3 id='justify-self-property'>
-Inline-Axis (or Main-Axis) Alignment: the 'justify-self' property</h3>
+Inline-Axis (or Main-Axis) Self-Alignment: the 'justify-self' property</h3>
 
 	<pre class="propdef">
 	Name: justify-self
@@ -1577,7 +1577,7 @@ Inline-Axis (or Main-Axis) Alignment: the 'justify-self' property</h3>
 	See [[!CSS-GRID-1]] for details.
 
 <h3 id='align-self-property'>
-Block-Axis (or Cross-Axis) Alignment: the 'align-self' property</h3>
+Block-Axis (or Cross-Axis) Self-Alignment: the 'align-self' property</h3>
 
 	<pre class="propdef">
 	Name: align-self
@@ -1923,7 +1923,7 @@ Default Alignment</h2>
 	</div>
 
 <h3 id='justify-items-property'>
-Inline-Axis (or Main-Axis) Alignment: the 'justify-items' property</h3>
+Inline-Axis (or Main-Axis) Default Alignment: the 'justify-items' property</h3>
 
 	<pre class="propdef">
 	Name: justify-items
@@ -1960,7 +1960,7 @@ Inline-Axis (or Main-Axis) Alignment: the 'justify-items' property</h3>
 	Other values have no special handling and are merely referenced by 'justify-self'.
 
 <h3 id='align-items-property'>
-Block-Axis (or Cross-Axis) Alignment: the 'align-items' property</h3>
+Block-Axis (or Cross-Axis) Default Alignment: the 'align-items' property</h3>
 
 	<pre class="propdef">
 	Name: align-items
@@ -1980,7 +1980,7 @@ Block-Axis (or Cross-Axis) Alignment: the 'align-items' property</h3>
 	Values have no special handling and are merely referenced by 'align-self'.
 
 <h3 id='place-items-property'>
-Self-Alignment Shorthand: the 'place-items' property</h3>
+Default Alignment Shorthand: the 'place-items' property</h3>
 
 	<pre class="propdef">
 	Name: place-items