[css-anchor-position][editorial] Fix headings. #9179

Author: tabatkins

css-anchor-position-1/Overview.bs

@@ -101,7 +101,7 @@ This can be done with the following CSS:
 	</pre>
 </div>
 
-Determining The Anchor {#determining}
+Determining the Anchor {#determining}
 ======================
 
 <!-- Big Text: a-name
@@ -115,7 +115,7 @@ Determining The Anchor {#determining}
 █▌  █▌       █▌   ▐▌ █▌  █▌ █▌   ▐█ █████▌
 -->
 
-Creating An Anchor: the 'anchor-name' property {#name}
+Creating an Anchor: the 'anchor-name' property {#name}
 ----------------------------------------------
 
 <pre class=propdef>
@@ -178,7 +178,7 @@ as its [=originating element=].
 Note: Without this, these [=pseudo-elements=], which are often inaccessible
 by other specifications, cannot be positioned with [=implicit anchor elements=].
 
-Finding An Anchor {#target}
+Finding an Anchor {#target}
 -----------------
 
 Several things in this specification
@@ -439,7 +439,7 @@ Its syntax is:
 
 
 <h4 id=resolving-spans>
-Resolving <<inset-area-span>>s</h4>
+Resolving <<inset-area>>s</h4>
 
 The <dfn export>inset-area grid</dfn> is a 3x3 grid,
 composed of four grid lines in each axis.
@@ -899,7 +899,7 @@ it resolves to ''0px''.
 █▌  █▌        ███▌  ████ █████▌ █████▌   ██ ██  
 -->
 
-Anchor-based Sizing {#sizing}
+Anchor-Based Sizing {#sizing}
 ===================
 
 An [=absolutely-positioned=] element
@@ -1755,7 +1755,7 @@ using existing JS APIs (such as {{Element/getBoundingClientRect()}}).
 DOM Interfaces {#interfaces}
 ==========
 
-The CSSPositionFallbackRule interface {#position-fallback-rule}
+The CSSPositionTryRule interface {#om-position-try}
 -------------------------------------
 
 The {{CSSPositionTryRule}} interface represents