docs: make the front page a landing page

docs/Limitations.wikitext

@@ -0,0 +1,36 @@
+__TOC__
+
+<languages />
+<translate>
+<!--T:1-->
+A published {{SITENAME}} site is files: HTML, CSS, JavaScript and images, with nothing running
+behind them. Anything MediaWiki does by answering a request when a reader asks for it is therefore
+not part of the export. This page is the list, and what stands in for each where anything does.
+
+<!--T:2-->
+== What a live wiki does and an export does not ==
+
+<!--T:3-->
+* All special pages, and the action API behind them
+* All editors ([<tvar name="1">https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:WikiEditor</tvar> WikiEditor], <!--
+-->[<tvar name="2">https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:VisualEditor</tvar> VisualEditor] and <!--
+-->[<tvar name="3">https://www.mediawiki.org/wiki/Special:MyLanguage/Extension:CodeEditor</tvar> CodeEditor]); you edit the source files instead
+* Accounts, and everything keyed to one: preferences, watchlists, notifications, user pages
+* Page histories and diffs
+* Discussion pages as a workflow, and recent-changes feeds
+
+<!--T:4-->
+== What stands in for them ==
+
+<!--T:5-->
+; Editing and history
+: Your repository. The "Edit", "View history" and "View source" links on each page lead to the page's source file there, wherever you host it; see [[<tvar name="1">Special:MyLanguage/Configuration#WikvenEditUrl</tvar>|<code>WikvenEditUrl</code>]] and the two settings beside it.
+; Reading preferences
+: A [[<tvar name="2">Special:MyLanguage/Skins#Settings</tvar>|Settings page]] the build writes, carrying the reader's colour theme and, where a site builds more than one skin, which skin to read it in.
+; Search
+: [[<tvar name="3">Special:MyLanguage/Searching</tvar>|Done in the browser]]. The build writes a search index alongside the pages and the search box queries that.
+; <code>Special:Version</code>
+: The [[<tvar name="4">Special:MyLanguage/Configuration#WikvenAboutPage</tvar>|About page]], where the build lists the software, extensions and skins the site was made with.
+</translate>
+
+{{prevnext}}

docs/Limitations/ko.wikitext

@@ -0,0 +1,28 @@
+<!--T:title @69b1b67d-->
+제한 사항
+
+<!--T:1 @37e7d790-->
+게시된 {{SITENAME}} 사이트는 파일입니다. HTML, CSS, JavaScript, 이미지가 있을 뿐 그 뒤에서 돌아가는 것은 없습니다. 그래서 MediaWiki가 독자의 요청을 그때그때 받아 처리하던 일은 내보내기에 포함되지 않습니다. 이 문서가 그 목록이며, 대신할 것이 있는 경우 무엇이 대신하는지도 함께 적었습니다.
+
+<!--T:2 @2efabce0-->
+== 구동 중인 위키는 하고 내보내기는 못하는 것 ==
+
+<!--T:3 @d3ddb863-->
+* 모든 특수 문서와 그 뒤의 action API
+* 모든 편집기 ([$1 WikiEditor], [$2 시각편집기], [$3 CodeEditor]). 대신 소스 파일을 편집합니다
+* 계정, 그리고 계정에 딸린 모든 것: 환경 설정, 주시문서 목록, 알림, 사용자 문서
+* 문서 역사와 차이
+* 작업 흐름으로서의 토론 문서, 그리고 최근 바뀜 피드
+
+<!--T:4 @0fe9634e-->
+== 그 자리를 대신하는 것 ==
+
+<!--T:5 @644f91a8-->
+; 편집과 역사
+: 리포지터리입니다. 각 문서의 "편집", "역사 보기", "원본 보기" 링크는 어디에 두었든 그곳의 소스 파일로 이어집니다. [[$1|<code>WikvenEditUrl</code>]]과 그 옆의 두 설정을 참고하세요.
+; 표시 설정
+: 빌드가 쓰는 [[$2|설정 문서]]로, 독자의 색 테마와, 스킨을 여러 개 빌드한 사이트라면 어떤 스킨으로 읽을지를 담고 있습니다.
+; 검색
+: [[$3|브라우저에서]] 이루어집니다. 빌드가 문서 옆에 검색 색인을 함께 쓰고, 검색창은 그 색인에 질의합니다.
+; <code>Special:Version</code>
+: [[$4|소개 문서]]입니다. 사이트를 만드는 데 쓰인 소프트웨어·확장 기능·스킨을 빌드가 여기에 나열합니다.

docs/MediaWiki:Common.css

@@ -175,3 +175,198 @@ body:not(.skin-citizen) .mw-parser-output a.external {
 #footer-places-desktop-toggle {
 	display: none;
 }
+
+/* The landing page's filled button, defined here because TemplateStyles drops a custom-property
+ * declaration and so cannot make a token, only read one. It has to be a pair and it has to
+ * invert: night mode moves --color-progressive to a pale teal that white text sits on at
+ * 2.07:1, while the brand teal it replaces sits on the night ground at 3.2:1 -- so a button
+ * pinned to either one stops being the loudest thing on the page in half the sessions. Light
+ * teal with near-black text is 8.9:1 against both the text and the ground.
+ *
+ * Scoped to the landing page by its root-page class, which is the one the translations carry
+ * too: the body of index/ko is page-index_ko, and only rootpage-index catches both. The
+ * selectors are core's own darkmode-override() pair, the same as the tokens above. */
+.rootpage-index .mw-parser-output {
+	--wikven-cta-bg: #10707f;
+	--wikven-cta-bg--hover: #0d5c68;
+	--wikven-cta-fg: #fff;
+}
+
+@media screen {
+	html.skin-theme-clientpref-night .rootpage-index .mw-parser-output {
+		--wikven-cta-bg: #4ec3da;
+		--wikven-cta-bg--hover: #79d0e0;
+		--wikven-cta-fg: #101418;
+	}
+}
+
+@media screen and (prefers-color-scheme: dark) {
+	html.skin-theme-clientpref-os .rootpage-index .mw-parser-output {
+		--wikven-cta-bg: #4ec3da;
+		--wikven-cta-bg--hover: #79d0e0;
+		--wikven-cta-fg: #101418;
+	}
+}
+
+/* The landing page sets its own tagline where a page title would go, so the title is taken out
+ * of the flow there and nowhere else.
+ *
+ * MediaWiki has a native way to do exactly this -- blanking MediaWiki:Mainpage-title and
+ * MediaWiki:Mainpage-title-loggedin -- and this site cannot use it. Those messages are only read
+ * for the page Title::isMainPage() is true of, and MediaWiki:Mainpage here holds
+ * "Special:MyLanguage/index" rather than "index", so that every skin's logo follows the reader's
+ * language; the cost of that, which Editing sidebar sets out, is that the wiki stops recognising
+ * the page as its main page. Keeping the logo is worth more than saving these seven lines.
+ *
+ * Clipped rather than display: none, so the heading stays in the accessibility tree: the page
+ * still has its h1 for a reader who is not looking at it, and only the sighted reader is spared
+ * the site name twice over.
+ *
+ * Here rather than in the page's own TemplateStyles because TemplateStyles prefixes every
+ * selector with .mw-parser-output and the heading is outside the parser output. rootpage- so
+ * that the translations (index/ko) are covered by the same rule as the source page; page- as
+ * well, so the source page is covered even where the root class is not written. */
+.page-index #firstHeading,
+.rootpage-index #firstHeading {
+	position: absolute;
+	overflow: hidden;
+	clip-path: inset(50%);
+	inline-size: 1px;
+	block-size: 1px;
+	white-space: nowrap;
+}
+
+/* The diagram's file-type marks, and the caret in the command beside them.
+ *
+ * Both are here rather than in the page's own TemplateStyles because that file can carry
+ * neither: a mask-image is not colour-typed, so a var() in one cannot be checked and the whole
+ * declaration is dropped, and @keyframes is not a rule it can rely on either. This file is not
+ * sanitised, and the external-link arrow above is already a data-URI SVG, so the mechanism is one
+ * the site has proven.
+ *
+ * Masks rather than images, and rather than a filter. An uploaded SVG placed with [[File:...]] is
+ * a fixed-colour picture that cannot follow the theme -- the problem the arrow above solves by
+ * carrying two copies of itself -- and a filter could only invert or rotate the colours the file
+ * already has, which a set of five does not survive. A mask throws the source's colours away and
+ * paints the shape in whatever colour the rule gives it, so two glyphs serve every type in both
+ * themes.
+ *
+ * Only the four named types are marked. Anything else keeps the space, so the names in a tree
+ * still start on the same edge, and nothing is drawn in it. */
+.rootpage-index .wikven-home-f::before {
+	content: "";
+	display: inline-block;
+	inline-size: 1rem;
+	block-size: 1rem;
+	margin-inline-end: 0.45rem;
+	vertical-align: -0.18rem;
+}
+
+.rootpage-index .wikven-home-f--wikitext::before,
+.rootpage-index .wikven-home-f--html::before,
+.rootpage-index .wikven-home-f--css::before,
+.rootpage-index .wikven-home-f--dir::before {
+	-webkit-mask:
+		url("data:image/svg+xml,<svg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%2016%2016'><path%20d='M9.4%201.6H4.2a.6.6%200%200%200-.6.6v11.6a.6.6%200%200%200%20.6.6h7.6a.6.6%200%200%200%20.6-.6V4.6zM9.4%201.6v3h3'%20fill='none'%20stroke='%23000'%20stroke-width='1.3'%20stroke-linejoin='round'/></svg>")
+		no-repeat center / contain;
+	mask:
+		url("data:image/svg+xml,<svg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%2016%2016'><path%20d='M9.4%201.6H4.2a.6.6%200%200%200-.6.6v11.6a.6.6%200%200%200%20.6.6h7.6a.6.6%200%200%200%20.6-.6V4.6zM9.4%201.6v3h3'%20fill='none'%20stroke='%23000'%20stroke-width='1.3'%20stroke-linejoin='round'/></svg>")
+		no-repeat center / contain;
+}
+
+.rootpage-index .wikven-home-f--dir::before {
+	-webkit-mask-image: url("data:image/svg+xml,<svg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%2016%2016'><path%20d='M1.7%203.4h4.1l1.6%202h6.9v7.2H1.7z'%20fill='none'%20stroke='%23000'%20stroke-width='1.3'%20stroke-linejoin='round'/></svg>");
+	mask-image: url("data:image/svg+xml,<svg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%2016%2016'><path%20d='M1.7%203.4h4.1l1.6%202h6.9v7.2H1.7z'%20fill='none'%20stroke='%23000'%20stroke-width='1.3'%20stroke-linejoin='round'/></svg>");
+}
+
+/* .wikitext takes the brand teal, which makes the source pane one colour against a mixed output
+ * pane: one kind of thing goes in and several come out, said in colour rather than in a sentence.
+ * The other three are their own conventions, darkened for the light ground and lifted for the
+ * night one. These are graphics and want 3:1, which every pair here clears on both grounds. */
+.rootpage-index .wikven-home-f--wikitext::before {
+	background-color: #10707f;
+}
+
+.rootpage-index .wikven-home-f--html::before {
+	background-color: #b3541e;
+}
+
+.rootpage-index .wikven-home-f--css::before {
+	background-color: #2b6cb0;
+}
+
+.rootpage-index .wikven-home-f--dir::before {
+	background-color: #54595d;
+}
+
+@media screen {
+	html.skin-theme-clientpref-night
+		.rootpage-index
+		.wikven-home-f--wikitext::before {
+		background-color: #4ec3da;
+	}
+
+	html.skin-theme-clientpref-night
+		.rootpage-index
+		.wikven-home-f--html::before {
+		background-color: #e8a06a;
+	}
+
+	html.skin-theme-clientpref-night .rootpage-index .wikven-home-f--css::before {
+		background-color: #7fb3f0;
+	}
+
+	html.skin-theme-clientpref-night .rootpage-index .wikven-home-f--dir::before {
+		background-color: #a2a9b1;
+	}
+}
+
+@media screen and (prefers-color-scheme: dark) {
+	html.skin-theme-clientpref-os
+		.rootpage-index
+		.wikven-home-f--wikitext::before {
+		background-color: #4ec3da;
+	}
+
+	html.skin-theme-clientpref-os .rootpage-index .wikven-home-f--html::before {
+		background-color: #e8a06a;
+	}
+
+	html.skin-theme-clientpref-os .rootpage-index .wikven-home-f--css::before {
+		background-color: #7fb3f0;
+	}
+
+	html.skin-theme-clientpref-os .rootpage-index .wikven-home-f--dir::before {
+		background-color: #a2a9b1;
+	}
+}
+
+/* The caret is what makes the middle of the diagram read as a command rather than as a label with
+ * a dollar sign in front of it. A reader who has asked for less motion gets it still. */
+@keyframes wikven-caret {
+	0%,
+	100% {
+		opacity: 1;
+	}
+
+	50% {
+		opacity: 0;
+	}
+}
+
+.rootpage-index .wikven-home-machine::after {
+	content: "";
+	display: inline-block;
+	inline-size: 0.55em;
+	block-size: 1.05em;
+	margin-inline-start: 0.35em;
+	vertical-align: -0.2em;
+	background-color: currentcolor;
+	animation: wikven-caret 1.1s step-end infinite;
+}
+
+@media (prefers-reduced-motion: reduce) {
+	.rootpage-index .wikven-home-machine::after {
+		animation: none;
+	}
+}

docs/MediaWiki:Sidebar-limitations.wikitext

@@ -0,0 +1 @@
+Limitations

docs/MediaWiki:Sidebar-limitations/ko.wikitext

@@ -0,0 +1 @@
+제한 사항

docs/MediaWiki:Sidebar.wikitext

@@ -20,6 +20,7 @@
 ** Special:MyLanguage/Deploying|sidebar-deploying
 ** Special:MyLanguage/Troubleshooting|sidebar-troubleshooting
 * sidebar-references
+** Special:MyLanguage/Limitations|sidebar-limitations
 ** Special:MyLanguage/Configuration|sidebar-configuration
 ** Special:MyLanguage/Standalone binary|sidebar-standalone-binary
 ** Special:MyLanguage/Commands|sidebar-commands

docs/Template:home.wikitext

@@ -0,0 +1,3 @@
+<templatestyles src="home/styles.css" /><noinclude>
+{{home/doc}}
+</noinclude>