Migrate line numbers CSS to CSS variables

Author: GuillaumeGomez

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

@@ -571,10 +571,18 @@ ul.block, .block li {
 	padding: 13px 8px;
 	border-top-left-radius: 5px;
 	border-bottom-left-radius: 5px;
+	border-color: var(--example-line-numbers-border-color);
 }
 
 .src-line-numbers span {
 	cursor: pointer;
+	color: var(--src-line-numbers-span-color);
+}
+.src-line-numbers .line-highlighted {
+	background-color: var(--src-line-number-highlighted-background-color);
+}
+.src-line-numbers :target {
+	background-color: transparent;
 }
 
 .search-loading {

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

@@ -55,6 +55,9 @@ Original by Dempfi (https://github.com/dempfi/ayu)
 	--code-highlight-question-mark-color: #ff9011;
 	--code-highlight-comment-color: #788797;
 	--code-highlight-doc-comment-color: #a1ac88;
+	--example-line-numbers-border-color: none;
+	--src-line-numbers-span-color: #5c6773;
+	--src-line-number-highlighted-background-color: rgba(255, 236, 164, 0.06);
 }
 
 .slider {
@@ -112,10 +115,8 @@ pre, .rustdoc.source .example-wrap {
 	color: #ff7733;
 }
 
-.src-line-numbers span { color: #5c6773; }
 .src-line-numbers .line-highlighted {
 	color: #708090;
-	background-color: rgba(255, 236, 164, 0.06);
 	padding-right: 4px;
 	border-right: 1px solid #ffb44c;
 }
@@ -170,13 +171,6 @@ details.rustdoc-toggle > summary::before {
 	color: #788797;
 }
 
-.src-line-numbers :target { background-color: transparent; }
-
-pre.example-line-numbers {
-	color: #5c67736e;
-	border: none;
-}
-
 a.test-arrow {
 	font-size: 100%;
 	color: #788797;

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

@@ -50,6 +50,9 @@
 	--code-highlight-question-mark-color: #ff9011;
 	--code-highlight-comment-color: #8d8d8b;
 	--code-highlight-doc-comment-color: #8ca375;
+	--example-line-numbers-border-color: #4a4949;
+	--src-line-numbers-span-color: #3b91e2;
+	--src-line-number-highlighted-background-color: #0a042f;
 }
 
 .slider {
@@ -69,11 +72,6 @@ input:focus + .slider {
 		drop-shadow(0 -1px 0 #fff)
 }
 
-.src-line-numbers span { color: #3B91E2; }
-.src-line-numbers .line-highlighted {
-	background-color: #0a042f !important;
-}
-
 .content .item-info::before { color: #ccc; }
 
 body.source .example-wrap pre.rust a {
@@ -95,12 +93,6 @@ details.rustdoc-toggle > summary::before {
 	filter: invert(69%) sepia(60%) saturate(6613%) hue-rotate(184deg) brightness(100%) contrast(91%);
 }
 
-.src-line-numbers :target { background-color: transparent; }
-
-pre.example-line-numbers {
-	border-color: #4a4949;
-}
-
 a.test-arrow {
 	color: #dedede;
 	background-color: rgba(78, 139, 202, 0.2);

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

@@ -50,6 +50,9 @@
 	--code-highlight-question-mark-color: #ff9011;
 	--code-highlight-comment-color: #8e908c;
 	--code-highlight-doc-comment-color: #4d4d4c;
+	--example-line-numbers-border-color: #c7c7c7;
+	--src-line-numbers-span-color: #c67e2d;
+	--src-line-number-highlighted-background-color: #fdffd3;
 }
 
 .slider {
@@ -68,11 +71,6 @@ input:focus + .slider {
 	 */
 }
 
-.src-line-numbers span { color: #c67e2d; }
-.src-line-numbers .line-highlighted {
-	background-color: #FDFFD3 !important;
-}
-
 .content .item-info::before { color: #ccc; }
 
 body.source .example-wrap pre.rust a {
@@ -90,12 +88,6 @@ body.source .example-wrap pre.rust a {
 	filter: invert(44%) sepia(18%) saturate(23%) hue-rotate(317deg) brightness(96%) contrast(93%);
 }
 
-.src-line-numbers :target { background-color: transparent; }
-
-pre.example-line-numbers {
-	border-color: #c7c7c7;
-}
-
 a.test-arrow {
 	color: #f5f5f5;
 	background-color: rgba(78, 139, 202, 0.2);