Fix stylesheets in the rendering section

* Change :matches() to :is() per
  w3c/csswg-drafts#3258.
* Fix missing quotes in iframe[frameborder='0'] since 0 is not an ident
  or string.

Closes #5703.

source

@@ -112120,7 +112120,7 @@ tbody, tfoot, tr, td, th, dir, dd, dl, dt, menu, ol, ul, li, bdi, output,
 
 bdo, bdo[dir] { unicode-bidi: isolate-override; } <!-- bdo[dir] rule is to override the otherwise higher-specificity attribute selectors in the previous rule -->
 
-input[dir=auto i]:matches([type=search i], [type=tel i], [type=url i],
+input[dir=auto i]:is([type=search i], [type=tel i], [type=url i],
 [type=email i]), textarea[dir=auto i], pre[dir=auto i] {
   unicode-bidi: plaintext;
 }
@@ -112190,7 +112190,7 @@ h5 { margin-block-start: 1.67em; margin-block-end: 1.67em; font-size: 0.83em; fo
 h6 { margin-block-start: 2.33em; margin-block-end: 2.33em; font-size: 0.67em; font-weight: bold; }</code></pre>
 
   <p>In the following CSS block, <var>x</var> is shorthand for the following selector:
-  <code data-x="">:matches(article, aside, nav, section)</code></p>
+  <code data-x="">:is(article, aside, nav, section)</code></p>
 
   <pre><code class="css" data-x="">@namespace url(http://www.w3.org/1999/xhtml);
 
@@ -112227,7 +112227,7 @@ li { display: list-item; }<!-- see also unicode-bidi:isolate rules -->
 
 dir, dl, menu, ol, ul { margin-block-start: 1em; margin-block-end: 1em; }
 
-:matches(dir, dl, menu, ol, ul) :matches(dir, dl, menu, ol, ul) {
+:is(dir, dl, menu, ol, ul) :is(dir, dl, menu, ol, ul) {
   margin-block-start: 0; margin-block-end: 0;
 }
 
@@ -112239,10 +112239,10 @@ ol { list-style-type: decimal; }
 dir, menu, ul {
   list-style-type: disc;
 }
-:matches(dir, menu, ol, ul) :matches(dir, menu, ul) {
+:is(dir, menu, ol, ul) :is(dir, menu, ul) {
   list-style-type: circle;
 }
-:matches(dir, menu, ol, ul) :matches(dir, menu, ol, ul) :matches(dir, menu, ul) {
+:is(dir, menu, ol, ul) :is(dir, menu, ol, ul) :is(dir, menu, ul) {
   list-style-type: square;
 }</code></pre>
 
@@ -112506,7 +112506,7 @@ table {
 
   <pre><code class="css" data-x="">@namespace url(http://www.w3.org/1999/xhtml);
 
-:matches(table, thead, tbody, tfoot, tr) > form { display: none !important; }</code></pre>
+:is(table, thead, tbody, tfoot, tr) > form { display: none !important; }</code></pre>
 
   <hr>
 
@@ -112699,15 +112699,15 @@ input, select, textarea {
   text-align: initial;
 }
 
-input:matches([type=reset i], [type=button i], [type=submit i]), button {
+input:is([type=reset i], [type=button i], [type=submit i]), button {
   text-align: center;
 }
 
-input:matches([type=reset i], [type=button i], [type=submit i], [type=color i]), button {
+input:is([type=reset i], [type=button i], [type=submit i], [type=color i]), button {
   display: inline-block;
 }
 
-input:matches([type=radio i], [type=checkbox i], [type=reset i], [type=button i],
+input:is([type=radio i], [type=checkbox i], [type=reset i], [type=button i],
 [type=submit i], [type=color i], [type=search i]), select, button {
   box-sizing: border-box;
 }
@@ -113255,7 +113255,7 @@ img[align=right i] { margin-left: 3px; }</code></pre>
 
   <pre><code class="css" data-x="">@namespace url(http://www.w3.org/1999/xhtml);
 
-iframe[frameborder=0], iframe[frameborder=no i] { border: none; }
+iframe[frameborder='0'], iframe[frameborder=no i] { border: none; }
 
 embed[align=left i], iframe[align=left i], img[align=left i],
 input[type=image i][align=left i], object[align=left i] {