Migrate search tab title color to CSS variable

src/librustdoc/html/static/css/rustdoc.css

@@ -1287,6 +1287,7 @@ a.test-arrow:hover {
 #titles > button > div.count {
 	display: inline-block;
 	font-size: 1rem;
+	color: var(--search-tab-title-count-color);
 }
 
 #src-sidebar-toggle {

src/librustdoc/html/static/css/themes/ayu.css

@@ -45,6 +45,7 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--search-color: #fff;
 	--search-results-alias-color: #c5c5c5;
 	--search-results-grey-color: #999;
+	--search-tab-title-count-color: #888;
 	--stab-background-color: #314559;
 	--stab-code-color: #e6e1cf;
 	--code-highlight-kw-color: #ff7733;
@@ -175,10 +176,6 @@ pre, .rustdoc.source .example-wrap {
 	border-bottom: 1px solid rgba(242, 151, 24, 0.3);
 }
 
-#titles > button > div.count {
-	color: #888;
-}
-
 /* rules that this theme does not need to set, here to satisfy the rule checker */
 /* note that a lot of these are partially set in some way (meaning they are set
 individually rather than as a group) */

src/librustdoc/html/static/css/themes/dark.css

@@ -40,6 +40,7 @@
 	--search-color: #111;
 	--search-results-alias-color: #fff;
 	--search-results-grey-color: #ccc;
+	--search-tab-title-count-color: #888;
 	--stab-background-color: #314559;
 	--stab-code-color: #e6e1cf;
 	--code-highlight-kw-color: #ab8ac1;
@@ -96,10 +97,6 @@
 	background-color: #353535;
 }
 
-#titles > button > div.count {
-	color: #888;
-}
-
 .scraped-example-list .scrape-help {
 	border-color: #aaa;
 	color: #eee;

src/librustdoc/html/static/css/themes/light.css

@@ -40,6 +40,7 @@
 	--search-color: #000;
 	--search-results-alias-color: #000;
 	--search-results-grey-color: #999;
+	--search-tab-title-count-color: #888;
 	--stab-background-color: #fff5d6;
 	--stab-code-color: #000;
 	--code-highlight-kw-color: #8959a8;
@@ -93,10 +94,6 @@
 	border-top-color: #0089ff;
 }
 
-#titles > button > div.count {
-	color: #888;
-}
-
 .scraped-example-list .scrape-help {
 	border-color: #555;
 	color: #333;