Typos, and more tweaks.

Author: tabatkins

css3-flexbox/Overview.html

@@ -1851,14 +1851,14 @@ <h2 id=layout-algorithm><span class=secno>7. </span> Flexbox Layout
 
        <dt>&lsquo;<code class=css>max-content</code>&rsquo;
 
-       <dd>The maximum line length is infinity, constrained by the main and
+       <dd>The maximum line length is infinity, constrained by the min and
         max main size constraints of the flexbox.
 
        <dt>&lsquo;<code class=css>fit-content</code>&rsquo;
 
-       <dd>The maximum line length is the greater of the flexbox's main size
-        constraint and the smaller of the flexbox's maximum size constraint
-        and the available space.
+       <dd>The maximum line length is the greater of the flexbox's min size
+        constraint and the smaller of the flexbox's max size constraint and
+        the available space.
       </dl>
 
      <li>Collect as many consecutive flexbox items as possible, starting from
@@ -1880,7 +1880,8 @@ <h2 id=layout-algorithm><span class=secno>7. </span> Flexbox Layout
    <li>Find the actual main size of the flexbox. If the flexbox's main size
     doesn't rely on its contents, it's actual main size is calculated per the
     appropriate rules. Otherwise, its main size is the length of its longest
-    line.
+    line, calculated by summing the main sizes of the margin boxes of each
+    flexbox item in the line.
 
    <li>For each flexbox line, <a
     href="#resolve-the-flexible-lengths"><i>resolve the flexible

css3-flexbox/Overview.src.html

@@ -909,10 +909,10 @@ <h2 id='layout-algorithm'>
 						<dd>The maximum line length is the flexbox's minimum main size.</dd>
 
 						<dt>''max-content''</dt>
-						<dd>The maximum line length is infinity, constrained by the main and max main size constraints of the flexbox.</dd>
+						<dd>The maximum line length is infinity, constrained by the min and max main size constraints of the flexbox.</dd>
 
 						<dt>''fit-content''</dt>
-						<dd>The maximum line length is the greater of the flexbox's main size constraint and the smaller of the flexbox's maximum size constraint and the available space.</dd>
+						<dd>The maximum line length is the greater of the flexbox's min size constraint and the smaller of the flexbox's max size constraint and the available space.</dd>
 					</dt>
 				</li>
 
@@ -924,7 +924,7 @@ <h2 id='layout-algorithm'>
 			<p class='issue'>Define "size doesn't rely on its contents". This should be any &lt;length>, a &lt;percentage> that can be resolved, or ''fill-available''.</p>
 		</li>
 
-		<li>Find the actual main size of the flexbox.  If the flexbox's main size doesn't rely on its contents, it's actual main size is calculated per the appropriate rules.  Otherwise, its main size is the length of its longest line.</li>
+		<li>Find the actual main size of the flexbox.  If the flexbox's main size doesn't rely on its contents, it's actual main size is calculated per the appropriate rules.  Otherwise, its main size is the length of its longest line, calculated by summing the main sizes of the margin boxes of each flexbox item in the line.</li>
 
 		<li>For each flexbox line, <i>resolve the flexible lengths</i> of the items contained within it.  All flexbox items now have a final main size.  Update each item's hypothetical cross size based on this main size.</li>