:root {
  color-scheme: light;
  --color-canvas: #f7f8f6;
  --color-surface: #ffffff;
  --color-ink: #1d2730;
  --color-muted: #62707a;
  --color-line: #d9e0e2;
  --color-brand: #0f766e;
  --color-brand-hover: #0b5f59;
  --color-link: #155e9a;
  --color-code-bg: #17212b;
  --color-code-ink: #e8f0f2;
  --color-notice-bg: #edf6f2;
  --color-notice-line: #9fcfbe;
  --color-inline-code: #e8eeee;
  --font-ui: Inter, "PingFang SC", "Microsoft YaHei", ui-sans-serif, system-ui, sans-serif;
  --font-reading: "Noto Serif CJK SC", "Songti SC", "STSong", Georgia, ui-serif, serif;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --radius-control: 4px;
  --radius-card: 8px;
  --shadow-subtle: 0 6px 20px rgb(29 39 48 / 0.06);
  --content-max: 1200px;
  --reading-max: 720px;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --color-canvas: #11191e;
  --color-surface: #19242a;
  --color-ink: #e7eef0;
  --color-muted: #afbec4;
  --color-line: #394a52;
  --color-brand: #54cbb4;
  --color-brand-hover: #79dbc8;
  --color-link: #82cbff;
  --color-code-bg: #0c1318;
  --color-code-ink: #e5edef;
  --color-notice-bg: #17332d;
  --color-notice-line: #4d9d89;
  --color-inline-code: #27373d;
  --shadow-subtle: 0 6px 20px rgb(0 0 0 / 0.24);
}

@media (prefers-color-scheme: dark) {
  html:not([data-theme]) {
    color-scheme: dark;
    --color-canvas: #11191e;
    --color-surface: #19242a;
    --color-ink: #e7eef0;
    --color-muted: #afbec4;
    --color-line: #394a52;
    --color-brand: #54cbb4;
    --color-brand-hover: #79dbc8;
    --color-link: #82cbff;
    --color-code-bg: #0c1318;
    --color-code-ink: #e5edef;
    --color-notice-bg: #17332d;
    --color-notice-line: #4d9d89;
    --color-inline-code: #27373d;
    --shadow-subtle: 0 6px 20px rgb(0 0 0 / 0.24);
  }
}

* { box-sizing: border-box; }
html { background: var(--color-canvas); }
body { margin: 0; min-width: 320px; color: var(--color-ink); background: var(--color-canvas); font-family: var(--font-ui); }
a { color: var(--color-link); text-decoration-thickness: 1px; text-underline-offset: 0.16em; }
a:hover { color: var(--color-brand-hover); }
button, summary { font: inherit; }
button { cursor: pointer; }

.site-shell { width: min(calc(100% - 64px), var(--content-max)); margin-inline: auto; }
.skip-link { position: fixed; z-index: 20; top: 8px; left: 8px; padding: 8px 12px; transform: translateY(-160%); color: var(--color-surface); background: var(--color-ink); border-radius: var(--radius-control); }
.skip-link:focus { transform: translateY(0); }
.site-header { position: sticky; z-index: 10; top: 0; border-bottom: 1px solid var(--color-line); background: var(--color-surface); box-shadow: 0 1px 0 rgb(0 0 0 / 0.01); }
.header-inner { display: flex; min-height: 64px; align-items: center; gap: var(--space-5); }
.site-brand { color: var(--color-ink); font-size: 1.05rem; font-weight: 700; text-decoration: none; white-space: nowrap; }
.site-nav { display: flex; min-width: 0; flex: 1; align-items: center; gap: var(--space-4); overflow-x: auto; }
.site-nav a { color: var(--color-muted); font-size: 0.92rem; text-decoration: none; white-space: nowrap; }
.site-nav a:hover { color: var(--color-brand); }
.header-tools { display: flex; align-items: center; gap: var(--space-2); }
.language-menu, .article-language-switcher { position: relative; }
.language-menu summary, .article-language-switcher summary { cursor: pointer; color: var(--color-muted); font-size: 0.9rem; }
.language-menu ul, .article-language-switcher ul { position: absolute; z-index: 12; right: 0; min-width: 150px; margin: var(--space-2) 0 0; padding: var(--space-2); border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); box-shadow: var(--shadow-subtle); list-style: none; }
.language-menu li, .article-language-switcher li { margin: 0; padding: 4px 6px; }
.language-menu a, .article-language-switcher a { text-decoration: none; }
.mobile-navigation { display: none; position: relative; }
.mobile-navigation summary { display: grid; width: 40px; height: 40px; place-items: center; border: 1px solid var(--color-line); border-radius: var(--radius-control); color: var(--color-ink); cursor: pointer; list-style: none; }
.mobile-navigation summary::-webkit-details-marker { display: none; }
.mobile-navigation summary svg { width: 18px; height: 18px; }
.mobile-navigation nav { position: absolute; z-index: 12; top: 48px; right: 0; display: grid; min-width: 180px; padding: var(--space-2); border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); box-shadow: var(--shadow-subtle); }
.mobile-navigation nav a { padding: 8px; color: var(--color-ink); text-decoration: none; }
.icon-button { display: grid; width: 40px; height: 40px; place-items: center; padding: 0; border: 1px solid var(--color-line); border-radius: var(--radius-control); color: var(--color-ink); background: transparent; }
.icon-button:hover { border-color: var(--color-brand); color: var(--color-brand); }
.icon-button svg { width: 18px; height: 18px; }

.page-intro { padding-top: 64px; padding-bottom: var(--space-6); }
.page-intro.compact { padding-top: var(--space-7); }
.eyebrow { margin: 0 0 var(--space-2); color: var(--color-brand); font-size: 0.78rem; font-weight: 700; letter-spacing: 0.08em; }
h1, h2, h3, h4 { color: var(--color-ink); letter-spacing: 0; }
h1 { max-width: 760px; margin: 0; font-size: 40px; line-height: 1.15; }
h2 { margin: 0; font-size: 28px; line-height: 1.25; }
h3 { margin: 0; font-size: 22px; line-height: 1.32; }
h4 { font-size: 18px; }
.page-description, .article-summary { max-width: var(--reading-max); margin: var(--space-4) 0 0; color: var(--color-muted); font-size: 1.05rem; line-height: 1.7; }
.content-section { margin-top: var(--space-7); margin-bottom: var(--space-7); }
.section-heading { display: flex; align-items: baseline; justify-content: space-between; gap: var(--space-4); margin-bottom: var(--space-4); }
.category-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-3); }
.category-link { display: block; padding: var(--space-4); border-bottom: 1px solid var(--color-line); color: var(--color-ink); text-decoration: none; }
.category-link:hover { border-color: var(--color-brand); color: var(--color-brand); }
.article-list { display: grid; gap: var(--space-3); }
.article-card { display: grid; grid-template-columns: minmax(0, 1fr); gap: var(--space-4); padding: 20px; border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); box-shadow: none; transition: border-color 150ms ease, box-shadow 150ms ease; }
.article-card:hover { border-color: var(--color-brand); box-shadow: var(--shadow-subtle); }
.article-card-cover { width: 100%; max-height: 280px; object-fit: cover; border-radius: var(--radius-control); }
.article-card-content { display: grid; gap: var(--space-2); }
.article-card h3 a { color: var(--color-ink); text-decoration: none; }
.article-card h3 a:hover { color: var(--color-brand); }
.article-card p, .article-card time { margin: 0; color: var(--color-muted); }
.article-card time, .article-category { font-size: 0.86rem; }
.article-category { color: var(--color-brand); text-decoration: none; }
.pagination { display: flex; align-items: center; justify-content: space-between; gap: var(--space-4); margin-top: var(--space-6); color: var(--color-muted); }

.article-page { padding-top: var(--space-7); padding-bottom: var(--space-7); }
.article-header { max-width: var(--reading-max); }
.breadcrumbs { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-bottom: var(--space-4); font-size: 0.9rem; }
.article-summary { font-family: var(--font-reading); }
.article-meta { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-top: var(--space-5); color: var(--color-muted); font-size: 0.88rem; }
.article-language-switcher { display: inline-block; margin-top: var(--space-4); }
.article-language-switcher ul { left: 0; right: auto; }
.article-cover { display: block; width: 100%; max-width: var(--reading-max); max-height: 520px; margin-top: var(--space-6); object-fit: cover; border-radius: var(--radius-card); }
.article-layout { display: grid; grid-template-columns: minmax(0, var(--reading-max)) 200px; gap: var(--space-7); margin-top: var(--space-6); }
.article-body { min-width: 0; max-width: var(--reading-max); font-family: var(--font-reading); font-size: 18px; line-height: 1.8; overflow-wrap: anywhere; }
.article-body > :first-child { margin-top: 0; }
.article-body h2, .article-body h3, .article-body h4 { margin-top: 48px; scroll-margin-top: 88px; font-family: var(--font-ui); }
.article-body p { margin: 0 0 20px; }
.article-body a { text-decoration-thickness: 1px; }
.article-body blockquote { margin: 24px 0; padding: 12px 16px; border-left: 3px solid var(--color-brand); background: var(--color-notice-bg); }
.article-body blockquote > :last-child { margin-bottom: 0; }
.article-body pre { overflow-x: auto; padding: 16px; border-radius: var(--radius-control); color: var(--color-code-ink); background: var(--color-code-bg); }
.article-body code { padding: 0.12em 0.3em; border-radius: 3px; background: var(--color-inline-code); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
.article-body pre code { padding: 0; color: inherit; background: transparent; }
.article-body table { display: block; max-width: 100%; overflow-x: auto; border-collapse: collapse; }
.article-body th, .article-body td { min-width: 120px; padding: 8px 12px; border: 1px solid var(--color-line); }
.article-body th { background: var(--color-notice-bg); }
.article-body img { display: block; max-width: 100%; height: auto; margin: 24px 0; }
.article-toc { position: sticky; top: 88px; align-self: start; border-left: 1px solid var(--color-line); padding-left: var(--space-4); font-family: var(--font-ui); font-size: 0.9rem; }
.article-toc ol { margin: var(--space-3) 0 0; padding: 0; list-style: none; }
.article-toc li { margin: 6px 0; }
.article-toc .toc-level-3 { padding-left: 10px; }
.article-toc .toc-level-4 { padding-left: 20px; }
.not-found { min-height: 50vh; }
.primary-link { display: inline-block; margin-top: var(--space-5); padding: 10px 14px; border-radius: var(--radius-control); color: #fff; background: var(--color-brand); text-decoration: none; }
.site-footer { margin-top: var(--space-7); border-top: 1px solid var(--color-line); color: var(--color-muted); }
.footer-inner { display: flex; justify-content: space-between; padding-block: var(--space-5); font-size: 0.9rem; }
.tool-directory { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-4); }
.tool-card { display: grid; grid-template-columns: 36px minmax(0, 1fr); gap: var(--space-4); padding: 20px; border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); }
.tool-card > svg { width: 24px; height: 24px; color: var(--color-brand); }
.tool-card h2 { font-size: 20px; }
.tool-card h2 a { color: var(--color-ink); text-decoration: none; }
.tool-card h2 a:hover { color: var(--color-brand); }
.tool-card p { margin: var(--space-2) 0 0; color: var(--color-muted); line-height: 1.6; }
.tool-workspace { padding: var(--space-5); border: 1px solid var(--color-line); border-radius: var(--radius-card); background: var(--color-surface); }
.tool-columns, .tool-result-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--space-4); }
.tool-field { display: grid; gap: var(--space-2); margin: 0; color: var(--color-ink); font-weight: 600; }
.tool-field textarea { min-height: 280px; margin: 0; resize: vertical; color: var(--color-ink); background: var(--color-canvas); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.9rem; line-height: 1.55; }
.tool-toolbar { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-3); margin-top: var(--space-4); }
.tool-actions { display: flex; flex-wrap: wrap; gap: var(--space-2); }
.tool-actions button { width: auto; min-width: 0; margin: 0; padding: 9px 14px; border-radius: var(--radius-control); font-size: 0.92rem; }
.tool-hint, .tool-status { min-height: 1.5em; margin: var(--space-3) 0 0; font-size: 0.9rem; }
.tool-hint { color: var(--color-muted); }
.tool-status[data-state="error"] { color: #b42318; }
.tool-status[data-state="success"] { color: var(--color-brand); }
.json-tree-panel { margin-top: var(--space-5); padding-top: var(--space-5); border-top: 1px solid var(--color-line); }
.json-tree-panel h2 { font-size: 20px; }
.json-tree { max-height: 520px; margin-top: var(--space-3); padding: var(--space-4); overflow: auto; border: 1px solid var(--color-line); border-radius: var(--radius-control); background: var(--color-canvas); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.88rem; line-height: 1.55; }
.json-tree-item { min-width: max-content; }
.json-tree summary { cursor: pointer; color: var(--color-ink); }
.json-tree-children { margin-left: var(--space-4); padding-left: var(--space-3); border-left: 1px solid var(--color-line); }
.json-value { overflow-wrap: anywhere; }
.json-string { color: var(--color-brand); }
.json-number { color: var(--color-link); }
.json-boolean, .json-null { color: var(--color-muted); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
:focus-visible { outline: 3px solid var(--color-brand); outline-offset: 3px; }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; } }
@media (max-width: 1023px) { .article-layout { grid-template-columns: minmax(0, var(--reading-max)); } .article-toc { position: static; order: -1; max-width: var(--reading-max); border-left: 0; border-bottom: 1px solid var(--color-line); padding: 0 0 var(--space-4); } }
@media (max-width: 767px) { .site-shell { width: min(calc(100% - 32px), var(--content-max)); } .header-inner { gap: var(--space-2); } .site-brand { min-width: 0; overflow: hidden; text-overflow: ellipsis; } .site-nav { display: none; } .header-tools { margin-left: auto; } .mobile-navigation { display: block; } .page-intro { padding-top: var(--space-7); } h1 { font-size: 32px; } .category-grid, .tool-directory, .tool-columns, .tool-result-grid { grid-template-columns: 1fr; } .article-page { padding-top: var(--space-6); } .article-card, .tool-workspace { padding: 16px; } .tool-toolbar { align-items: stretch; flex-direction: column; } .tool-actions { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); } .tool-actions button { width: 100%; } .footer-inner { align-items: flex-start; flex-direction: column; gap: var(--space-2); } }