/* BlueDoc 0.4.0 — 通用文档中心、分类浏览与三栏阅读；无需外部字体或样式框架。 */
:root {
    color-scheme: light;
    --color-primary: #245cde;
    --color-text: #17233d;
    --color-muted: #66758c;
    --color-border: #e2e8f1;
    --color-surface: #fff;
    --color-background: #fff;
    --content-width: 960px;
    --color-soft: #edf3ff;
    --color-hover: #f1f4f8;
    --color-code: #f4f6f9;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html { scroll-padding-top: 24px; }
body { margin: 0; background: var(--color-background); color: var(--color-text); font: 16px/1.75 system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; overflow-wrap: anywhere; }
a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }
button, input, textarea { font: inherit; }
button, .button-link { display: inline-block; padding: 8px 16px; border: 1px solid var(--color-primary); border-radius: 8px; background: var(--color-primary); color: #fff; cursor: pointer; }
button:hover, .button-link:hover { background: #174bc6; text-decoration: none; }
input, textarea { width: 100%; min-width: 0; padding: 9px 12px; border: 1px solid var(--color-border); border-radius: 8px; background: var(--color-surface); color: var(--color-text); }
:focus-visible { outline: 3px solid #93b4fa; outline-offset: 3px; }
h1, h2, h3 { line-height: 1.35; }
h1 { margin: 12px 0; font-size: clamp(28px, 4vw, 40px); letter-spacing: -.035em; }
h2 { font-size: 23px; }
.icon { width: 24px; height: 24px; flex-shrink: 0; vertical-align: middle; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.skip-link { position: absolute; top: -100px; left: 16px; z-index: 50; padding: 8px 16px; background: var(--color-surface); border: 1px solid var(--color-primary); border-radius: 8px; }
.skip-link:focus { top: 12px; }
.site-header { background: var(--color-surface); border-bottom: 1px solid var(--color-border); }
.header-inner, .site-nav, .site-main, .site-footer { width: min(var(--content-width), calc(100% - 48px)); margin-inline: auto; }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding-block: 18px; }
.site-brand { display: flex; align-items: center; gap: 12px; color: var(--color-text); font-size: 19px; font-weight: 700; min-width: 0; }
.site-brand:hover { text-decoration: none; }
.brand-mark { display: grid; place-items: center; flex: 0 0 36px; height: 36px; background: var(--color-primary); color: #fff; border-radius: 10px; }
.site-search { display: flex; gap: 8px; width: 330px; flex-shrink: 0; }
.site-search button { flex-shrink: 0; }
.site-nav { display: flex; flex-wrap: wrap; gap: 8px 24px; padding-block: 0 14px; }
.site-nav a { color: var(--color-muted); font-size: 13px; }
.site-nav a[aria-current="page"] { color: var(--color-primary); font-weight: 600; }
.site-main { min-height: 55vh; padding-block: 40px 64px; }
.section-header { margin-bottom: 32px; }
.eyebrow { margin: 0; color: var(--color-primary); font-size: 12px; font-weight: 600; letter-spacing: .08em; }
.section-description, .muted { color: var(--color-muted); }
.section-description { margin: 12px 0 0; }
.back-link { font-size: 14px; }

/* 首页负责找路：分类入口、阅读目录与推荐，不输出博客文章流。 */
.home-main { --content-width: 1120px; padding-top: 0; }
.home-hero { padding: 64px 20px 48px; text-align: center; background: radial-gradient(ellipse at 50% 20%, #eaf0ff, transparent 70%); }
.home-hero h1 { font-size: clamp(36px, 5vw, 54px); margin-top: 18px; }
.hero-description { color: var(--color-muted); font-size: 17px; max-width: 660px; margin: 16px auto 28px; }
.hero-search { display: flex; align-items: center; gap: 10px; max-width: 690px; margin-inline: auto; padding: 8px; border: 1px solid var(--color-border); border-radius: 12px; background: var(--color-surface); box-shadow: 0 8px 28px #233e7910; }
.search-icon { color: var(--color-muted); margin-left: 10px; }
.hero-search input { border: 0; padding: 10px 8px; }
.hero-search button { flex-shrink: 0; padding-inline: 24px; }
.hero-hint { color: var(--color-muted); font-size: 12px; margin-top: 14px; }
.home-section { margin-top: 38px; }
.home-section-heading { display: flex; align-items: end; justify-content: space-between; gap: 16px; margin-bottom: 20px; }
.home-section-heading h2 { margin: 6px 0 0; font-size: 24px; }
.home-section-heading > p { margin: 0; font-size: 13px; color: var(--color-muted); }
.quick-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(200px, 100%), 1fr)); gap: 14px; }
.category-grid, .popular-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.quick-card, .category-card, .popular-card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: 12px; color: var(--color-text); }
.quick-card:focus-within, .category-card:focus-within, .popular-card:hover { border-color: #97b5f3; }
.quick-card { display: flex; flex-direction: column; position: relative; gap: 12px; padding: 22px 16px; }
.quick-card-heading { display: flex; align-items: center; gap: 12px; color: var(--color-text); }
.quick-card-heading strong { min-width: 0; }
.quick-card strong { font-size: 17px; }
.quick-card small { color: var(--color-muted); font-size: 12px; margin-top: 4px; }
.quick-description { margin: 0; color: var(--color-muted); font-size: 12px; }
.quick-documents { list-style: none; padding: 10px 0 0; margin: 0; border-top: 1px solid var(--color-border); }
.quick-documents a { display: block; padding: 5px 0; font-size: 13px; color: var(--color-muted); }
.entry-mark { display: grid; place-items: center; flex: 0 0 40px; height: 40px; border-radius: 10px; background: var(--color-soft); color: var(--color-primary); }
.quick-card .card-arrow { position: absolute; top: 7px; right: 10px; font-size: 13px; }
.card-arrow { color: var(--color-primary); }
.category-card, .popular-card { display: flex; flex-direction: column; padding: 24px; }
.category-symbol { display: grid; place-items: center; align-self: start; width: 42px; height: 42px; color: var(--color-primary); border-radius: 10px; background: var(--color-soft); }
.category-card h3, .popular-card h3 { margin: 16px 0 8px; font-size: 18px; }
.category-card h3 a { color: var(--color-text); }
.category-card p { margin: 0 0 16px; color: var(--color-muted); font-size: 13px; }
.category-card small { color: var(--color-muted); margin-top: auto; font-size: 12px; }
.category-children { list-style: none; padding: 0; margin: 0 0 18px; }
.category-children a { display: flex; justify-content: space-between; gap: 8px; padding: 4px 0; font-size: 13px; color: var(--color-muted); }
.category-card-footer { display: flex; justify-content: space-between; align-items: center; gap: 10px; margin-top: auto; padding-top: 14px; border-top: 1px solid var(--color-border); font-size: 12px; }
.popular-category { color: var(--color-muted); font-size: 12px; }
.popular-card .read-link { margin-top: auto; padding-top: 14px; color: var(--color-primary); }

/* 正文与分类概览共用阅读组件。 */
.site-main.document-main { width: 100%; min-width: 0; margin: 0; padding: 0; }
.document-toc { position: sticky; overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; }
.sidebar-heading { display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px; }
.sidebar-heading h2, .document-toc h2 { font-size: 12px; color: var(--color-muted); margin: 0; font-weight: 600; }
.tree-home { display: block; margin-bottom: 14px; padding: 7px 10px; font-size: 13px; }
.tree-all { margin-top: 20px; border-top: 1px solid var(--color-border); padding-top: 16px; }
.tree-category { margin: 3px 0; }
.tree-category > summary { display: flex; align-items: center; justify-content: space-between; gap: 8px; padding: 8px 10px; border-radius: 7px; font-size: 13px; cursor: pointer; list-style: none; }
.tree-category > summary > span:first-child { min-width: 0; }
.tree-category > summary::-webkit-details-marker { display: none; }
.tree-category > summary:hover { background: var(--color-hover); }
.tree-category.is-active-branch > summary { font-weight: 600; }
.tree-chevron { flex-shrink: 0; color: var(--color-muted); font-size: 20px; line-height: 1; }
.tree-category[open] > summary .tree-chevron { transform: rotate(90deg); }
.tree-branch { margin: 2px 0 8px 8px; padding-left: 8px; border-left: 1px solid var(--color-border); }
/* 深层分类继续嵌套，但第五层之后停止增加缩进，保留可读宽度。 */
.tree-branch .tree-branch .tree-branch .tree-branch .tree-branch { margin-left: 0; padding-left: 0; }
.tree-overview { display: block; padding: 5px 9px; border-radius: 6px; font-size: 12px; color: var(--color-muted); }
.tree-posts { list-style: none; padding: 0; margin: 0; }
.tree-document { display: block; padding: 7px 9px; border-radius: 6px; font-size: 13px; color: var(--color-muted); line-height: 1.6; }
.tree-document:hover, .tree-overview:hover { color: var(--color-primary); background: var(--color-hover); text-decoration: none; }
.tree-document.is-current, .tree-overview.is-current { background: var(--color-soft); color: var(--color-primary); font-weight: 600; }
.tree-empty { color: var(--color-muted); font-size: 12px; padding: 5px 9px; margin: 0; }
.breadcrumbs { margin-bottom: 24px; color: var(--color-muted); font-size: 12px; }
.breadcrumbs ol { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 0; list-style: none; padding: 0; margin: 0; }
.breadcrumbs li + li::before { content: '›'; margin-inline: 8px; color: var(--color-muted); }
.breadcrumbs a { color: var(--color-muted); }
.breadcrumbs [aria-current="page"] { color: var(--color-text); }
.category-chip { padding: 1px 9px; border-radius: 5px; background: var(--color-soft); color: var(--color-muted); }
.document-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 12px; color: var(--color-muted); font-size: 12px; }
.document-meta a { color: inherit; }
.document { padding: 32px; border: 1px solid var(--color-border); border-radius: 12px; background: var(--color-surface); }
.document-content h2, .document-content h3 { scroll-margin-top: 28px; }
.document-content h2, .document-content h3, .document-content h4 { margin-top: 1.8em; }
.document-content > :first-child { margin-top: 0; }
.document-content img, .document-content video { max-width: 100%; height: auto; }
.document-content iframe { max-width: 100%; }
.document-content pre { padding: 18px; overflow-x: auto; border-radius: 8px; background: var(--color-code); }
.document-content code { padding: 2px 5px; border-radius: 4px; background: var(--color-code); font: .9em ui-monospace, SFMono-Regular, Consolas, monospace; }
.document-content pre code { padding: 0; background: transparent; }
.document-content blockquote { margin-inline: 0; padding: 4px 20px; border-left: 3px solid var(--color-primary); color: var(--color-muted); }
.document-content table { display: block; max-width: 100%; overflow-x: auto; border-collapse: collapse; }
.document-content th, .document-content td { padding: 10px 14px; border: 1px solid var(--color-border); }
.document-content hr { margin-block: 28px; border: 0; border-top: 1px solid var(--color-border); }
.document-toc { padding-top: 12px; }
.toc-list { list-style: none; padding: 0; margin: 16px 0 0; border-left: 1px solid var(--color-border); }
.toc-list a { display: block; padding: 6px 12px; margin-left: -1px; border-left: 2px solid transparent; color: var(--color-muted); font-size: 12px; line-height: 1.5; }
.toc-subheading a { padding-left: 24px; }
.toc-list a:hover { color: var(--color-primary); text-decoration: none; }
.toc-list a[aria-current="location"] { color: var(--color-primary); border-left-color: var(--color-primary); }
.toc-empty { font-size: 12px; color: var(--color-muted); }
.drawer-toggle, .drawer-close, .drawer-backdrop { display: none; }
.category-overview { background: var(--color-surface); padding: 32px; border: 1px solid var(--color-border); border-radius: 12px; }
.category-count { font-size: 12px; color: var(--color-muted); }
.subcategory-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.subcategory-card { display: flex; flex-direction: column; gap: 10px; padding: 18px; color: var(--color-text); border: 1px solid var(--color-border); border-radius: 8px; }
.subcategory-card:hover { border-color: #97b5f3; text-decoration: none; }
.subcategory-card small { display: flex; justify-content: space-between; gap: 10px; color: var(--color-muted); font-size: 12px; }
.category-documents { margin-top: 28px; }
.guide-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--color-border); }
.guide-list a { display: flex; justify-content: space-between; gap: 16px; padding: 16px 4px; color: var(--color-text); border-bottom: 1px solid var(--color-border); }
.guide-list a:hover { color: var(--color-primary); }
.guide-category { display: block; color: var(--color-muted); font-size: 12px; margin-top: 4px; }
.document-list { display: grid; gap: 0; background: var(--color-surface); border: 1px solid var(--color-border); border-radius: 12px; }
.document-card { padding: 20px 24px; }
.document-card + .document-card { border-top: 1px solid var(--color-border); }
.document-card h2 { margin: 6px 0; font-size: 18px; }
.document-card h2 a { color: var(--color-text); }
.document-card h2 a:hover { color: var(--color-primary); }
.read-link { font-size: 12px; font-weight: 600; }
.empty-state { padding: 32px 20px; border: 1px dashed var(--color-border); border-radius: 12px; background: var(--color-surface); text-align: center; color: var(--color-muted); }
.page-navigator { display: flex; flex-wrap: wrap; gap: 8px; padding: 0; margin: 28px 0 0; list-style: none; }
.page-navigator a, .page-navigator span { display: block; padding: 5px 12px; border: 1px solid var(--color-border); border-radius: 6px; background: var(--color-surface); }
.page-navigator .current a { background: var(--color-primary); color: #fff; border-color: var(--color-primary); }
.site-footer { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 8px 24px; padding-block: 24px; border-top: 1px solid var(--color-border); color: var(--color-muted); font-size: 12px; }
.site-footer p { margin: 0; }

/* 全站统一工作区：侧栏固定，顶部路径和正文留在右侧。 */
:root { --sidebar-width: 268px; }
:root[data-color="dark"] {
    color-scheme: dark;
    --color-primary: #91b0ff;
    --color-text: #e3e8f1;
    --color-muted: #9daabd;
    --color-border: #303945;
    --color-surface: #1c222b;
    --color-background: #161b22;
    --color-soft: #252f43;
    --color-hover: #252d38;
    --color-code: #202731;
}
@media (prefers-color-scheme: dark) {
    :root:not([data-color]) { color-scheme: dark; --color-primary: #91b0ff; --color-text: #e3e8f1; --color-muted: #9daabd; --color-border: #303945; --color-surface: #1c222b; --color-background: #161b22; --color-soft: #252f43; --color-hover: #252d38; --color-code: #202731; }
}
.workspace { margin-left: var(--sidebar-width); min-width: 0; }
.site-header { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 64px; padding: 12px 32px; background: var(--color-background); }
.topbar-location { display: flex; align-items: center; gap: 12px; min-width: 0; }
.topbar-title { color: var(--color-muted); font-size: 13px; }
.site-header .breadcrumbs { margin: 0; }
.color-control { display: flex; align-items: center; gap: 4px; color: var(--color-muted); flex-shrink: 0; font-size: 13px; }
.color-control select { border: 0; padding: 6px 2px; background: var(--color-background); color: var(--color-text); font: inherit; max-width: 104px; }
.document-sidebar { position: fixed; top: 0; left: 0; bottom: 0; width: var(--sidebar-width); max-height: 100dvh; display: flex; flex-direction: column; padding: 24px 18px 16px; margin: 0; border-right: 1px solid var(--color-border); background: var(--color-background); overflow: hidden; z-index: 30; }
.document-sidebar .site-brand { font-size: 18px; padding: 0 2px; margin-bottom: 24px; }
.document-sidebar .brand-mark { flex-basis: 30px; height: 30px; font-size: 14px; background: #245cde; }
.document-sidebar .site-search { display: flex; gap: 0; width: 100%; margin-bottom: 24px; background: var(--color-hover); border: 1px solid transparent; border-radius: 8px; }
.site-search:focus-within { border-color: var(--color-primary); }
.site-search input { border: 0; background: transparent; font-size: 13px; padding: 10px; }
.site-search button { border: 0; padding: 8px; background: transparent; color: var(--color-muted); }
.site-search .icon { width: 18px; height: 18px; }
.sidebar-heading { flex-shrink: 0; margin-bottom: 10px; }
.document-tree { flex: 1; overflow-y: auto; scrollbar-width: thin; min-height: 80px; }
.sidebar-pages { display: grid; max-height: 22vh; overflow-y: auto; gap: 4px; border-top: 1px solid var(--color-border); margin-top: 16px; padding-top: 12px; }
.sidebar-pages:empty { display: none; }
.sidebar-pages a { padding: 5px 10px; color: var(--color-muted); font-size: 13px; }
.tree-home[aria-current="page"], .sidebar-pages [aria-current="page"] { color: var(--color-primary); background: var(--color-soft); border-radius: 6px; }
.site-main { width: min(1100px, calc(100% - 64px)); }
.site-footer { width: calc(100% - 64px); }
.home-main { padding-top: 0; }
.home-hero { padding: 64px 0 24px; background: none; }
.home-hero h1 { font-size: clamp(32px, 4vw, 46px); font-weight: 650; }
.hero-description { font-size: 16px; }
.hero-actions { display: flex; justify-content: center; flex-wrap: wrap; gap: 12px; margin: 24px 0; }
button, .button-link { background: #245cde; border-color: #245cde; }
.button-secondary { display: inline-block; padding: 8px 16px; border: 1px solid var(--color-border); color: var(--color-text); border-radius: 8px; }
.button-secondary:hover { background: var(--color-hover); text-decoration: none; }
.hero-search { max-width: 620px; border-radius: 8px; box-shadow: none; }
.quick-grid { grid-template-columns: repeat(auto-fit, minmax(min(220px, 100%), 1fr)); }
.home-section { margin-top: 48px; }
.home-section-heading h2 { font-size: 23px; }
.directory-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.directory-card { display: flex; flex-direction: column; padding: 22px; border: 1px solid var(--color-border); border-radius: 10px; min-width: 0; background: var(--color-surface); }
.directory-card h3 { margin: 0 0 12px; font-size: 17px; }
.directory-card h3 a { color: var(--color-text); }
.directory-list { list-style: none; margin: 0 0 12px; padding: 0; }
.directory-list a { display: block; padding: 11px 0; border-bottom: 1px solid var(--color-border); color: var(--color-text); font-size: 13px; }
.directory-more { margin-top: auto; font-size: 12px; padding-top: 10px; }
.document-shell { display: grid; grid-template-columns: minmax(0, 1fr) 190px; gap: 44px; width: min(1180px, calc(100% - 64px)); margin: 40px auto 56px; }
.category-shell { display: block; max-width: 900px; }
.document, .category-overview { padding: 0; border: 0; border-radius: 0; background: transparent; }
.document-main { min-width: 0; }
.document-toc { top: 96px; max-height: calc(100dvh - 120px); }
.document-content { line-height: 1.85; }
.document-content h2, .document-content h3 { scroll-margin-top: 90px; }
.document-content h2 { padding-bottom: 10px; border-bottom: 1px solid var(--color-border); }
.document-pagination { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--color-border); }
.document-pagination a { display: flex; flex-direction: column; gap: 8px; padding: 18px; border: 1px solid var(--color-border); border-radius: 8px; color: var(--color-text); }
.document-pagination a:hover { border-color: var(--color-primary); text-decoration: none; }
.document-pagination small { color: var(--color-muted); }
.document-next { text-align: right; }
.code-block { position: relative; }
.code-block pre { padding-top: 48px; }
.code-copy { position: absolute; top: 8px; right: 8px; padding: 4px 10px; border: 1px solid var(--color-border); background: var(--color-surface); color: var(--color-muted); font-size: 12px; }
.code-copy:hover { background: var(--color-hover); }
.copy-buffer { position: fixed; left: -9999px; top: 0; }
.document-content .doc-callout { border-left-width: 4px; border-radius: 6px; background: var(--color-soft); color: var(--color-text); padding: 14px 18px; }
.doc-callout .callout-title { margin: 0 0 8px; color: var(--color-primary); font-weight: 650; }
.doc-callout > :last-child { margin-bottom: 0; }
.document-content .callout-tip { border-left-color: #39a777; }
.document-content .callout-important { border-left-color: #9a78df; }
.document-content .callout-warning { border-left-color: #d59932; }
.document-content .callout-caution { border-left-color: #dd6969; }
@media (max-width: 1199px) {
    .category-grid, .popular-grid, .directory-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .document-shell { gap: 24px; grid-template-columns: minmax(0, 1fr) 156px; }
    .category-shell { display: block; }
}
@media (max-width: 1023px) {
    .document-toc { display: none; }
    .document-shell { display: block; }
    .site-header { padding-inline: 24px; }
    .site-main, .document-shell, .site-footer { width: calc(100% - 48px); }
}
@media (max-width: 767px) {
    .workspace { margin-left: 0; }
    .site-header { padding: 10px 16px; min-height: 58px; }
    .document-sidebar { position: static; width: 100%; max-height: none; border-right: 0; border-bottom: 1px solid var(--color-border); }
    .document-tree { max-height: 360px; }
    .has-drawer .document-sidebar { position: fixed; width: min(320px, 88vw); max-height: 100dvh; border-right: 1px solid var(--color-border); transform: translateX(-100%); visibility: hidden; }
    .has-drawer .document-tree { max-height: none; }
    .has-drawer .is-drawer-open .document-sidebar { transform: translateX(0); visibility: visible; }
    .is-drawer-open { overflow: hidden; }
    .has-drawer .drawer-toggle { display: inline-flex; align-items: center; justify-content: center; padding: 3px 8px; background: var(--color-surface); color: var(--color-text); border-color: var(--color-border); }
    .has-drawer .drawer-close { display: block; padding: 0 8px; border: 0; background: transparent; color: var(--color-text); font-size: 24px; }
    .drawer-backdrop { display: block; position: fixed; inset: 0; z-index: 25; padding: 0; border: 0; border-radius: 0; background: #11182780; }
    .drawer-backdrop:hover { background: #11182780; }
    .site-main, .document-shell, .site-footer { width: calc(100% - 32px); }
    .document-shell { margin-top: 28px; }
    .home-section-heading { display: block; }
    .home-section-heading > p { margin-top: 8px; }
    .home-hero { padding: 36px 0 16px; }
    .hero-search button { padding-inline: 14px; }
    .color-control select { max-width: 94px; font-size: 12px; }
    .site-header .breadcrumbs { font-size: 11px; }
}
@media (max-width: 480px) {
    .category-grid, .popular-grid, .directory-grid, .subcategory-grid { grid-template-columns: 1fr; }
    .quick-card { padding: 18px; }
    .hero-search { gap: 4px; padding: 6px; }
    .search-icon { display: none; }
    .hero-search input { padding-inline: 6px; font-size: 14px; }
    .hero-search button { padding-inline: 10px; font-size: 14px; }
    .document-pagination { gap: 10px; }
    .document-pagination a { padding: 12px; font-size: 13px; }
}