:root {
      --paper: #f7f3ea; --paper-2: #efe9db; --ink: #171512; --ink-soft: #5c574d;
      --line-soft: rgba(23, 21, 18, 0.16); --orange: #ff4d00; --orange-dark: #d63f00;
      --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-display: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-mono: "IBM Plex Mono", ui-monospace, monospace;
    }
    * { margin: 0; padding: 0; box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body { background: var(--paper); color: var(--ink); font-family: var(--font-sans); line-height: 1.8; overflow-x: hidden; }
    ::selection { background: var(--orange); color: var(--paper); }
    a { color: inherit; text-decoration: none; }
    ul, ol { list-style: none; }
    button { font-family: inherit; }
    .container { width: min(820px, calc(100% - 40px)); margin: 0 auto; }
    .wide { width: min(1200px, calc(100% - 40px)); margin: 0 auto; }
    .mono { font-family: var(--font-mono); }
    body::before { content: ""; position: fixed; inset: 0; pointer-events: none; z-index: 0; background-image: radial-gradient(rgba(23, 21, 18, 0.045) 1px, transparent 1px); background-size: 22px 22px; }
    main, header, footer, .ticker { position: relative; z-index: 1; }

    .ticker { background: var(--orange); color: var(--paper); font-family: var(--font-mono); font-size: 12.5px; font-weight: 700; letter-spacing: 1px; overflow: hidden; white-space: nowrap; padding: 7px 0; border-bottom: 2px solid var(--ink); }
    .ticker-track { display: inline-block; animation: ticker-scroll 32s linear infinite; }
    .ticker-track span { margin: 0 26px; }
    @keyframes ticker-scroll { from { transform: translateX(0); } to { transform: translateX(-50%); } }

    .nav { position: sticky; top: 0; z-index: 100; background: var(--paper); border-bottom: 2px solid var(--ink); }
    .nav-inner { display: flex; align-items: stretch; height: 62px; }
    .logo { display: flex; align-items: center; gap: 10px; font-family: var(--font-display); font-weight: 900; font-size: 21px; letter-spacing: 1px; padding-right: 28px; border-right: 2px solid var(--ink); }
    .logo img { display: block; width: 32px; height: 32px; object-fit: contain; }
    .nav-links { display: flex; align-items: stretch; }
    .nav-links a { display: flex; align-items: center; padding: 0 22px; font-size: 14.5px; font-weight: 500; border-right: 1px solid var(--line-soft); transition: background .15s, color .15s; }
    .nav-links a:hover { background: var(--ink); color: var(--paper); }
    .nav-links a.active { background: var(--orange); color: var(--paper); border-right-color: var(--ink); }
    .nav-drop { position: relative; display: flex; align-items: stretch; border-right: 1px solid var(--line-soft); }
    .nav-drop-trigger { display: flex; align-items: center; gap: 6px; height: 100%; padding: 0 22px; font-size: 14.5px; font-weight: 500; transition: background .15s, color .15s; }
    .nav-drop-trigger.active { background: var(--orange); color: var(--paper); }
    .nav-drop:hover .nav-drop-trigger { background: var(--ink); color: var(--paper); }
    .nav-drop-caret { flex-shrink: 0; transition: transform .15s; }
    .nav-drop:hover .nav-drop-caret { transform: rotate(180deg); }
    .nav-drop-menu { position: absolute; left: 0; top: 100%; background: var(--paper); border: 2px solid var(--ink); box-shadow: 5px 5px 0 var(--ink); min-width: 190px; display: none; z-index: 110; }
    .nav-drop:hover .nav-drop-menu { display: block; }
    .nav-drop-menu a { display: block; padding: 11px 16px; font-size: 13.5px; font-weight: 500; border-bottom: 1px solid var(--line-soft); color: var(--ink); }
    .nav-drop-menu a:last-child { border-bottom: none; }
    .nav-drop-menu a:hover { background: var(--paper-2); color: var(--orange); }
    .nav-right { margin-left: auto; display: flex; align-items: center; gap: 10px; }
    .lang-switch { position: relative; }
    .lang-btn { display: flex; align-items: center; gap: 7px; background: transparent; border: 1.5px solid var(--ink); color: var(--ink); padding: 7px 13px; font-size: 13px; font-family: var(--font-mono); cursor: pointer; transition: background .15s, color .15s; }
    .lang-btn:hover { background: var(--ink); color: var(--paper); }
    .lang-menu { position: absolute; right: 0; top: calc(100% + 10px); background: var(--paper); border: 2px solid var(--ink); box-shadow: 5px 5px 0 var(--ink); min-width: 150px; display: none; }
    .lang-menu.open { display: block; }
    .lang-menu a { display: block; padding: 9px 14px; font-size: 13.5px; cursor: pointer; border-bottom: 1px solid var(--line-soft); text-decoration: none; color: inherit; }
    .lang-menu a:last-child { border-bottom: none; }
    .lang-menu a:hover { background: var(--paper-2); }
    .lang-menu a.current { background: var(--orange); color: var(--paper); }
    .nav-toggle { display: none; background: none; border: 1.5px solid var(--ink); width: 40px; height: 40px; font-size: 17px; cursor: pointer; color: var(--ink); }
    .nav-mobile { display: none; }
    @media (max-width: 720px) {
      .nav-links { display: none; }
      .nav-toggle { display: block; }
      .nav-mobile { display: none; flex-direction: column; border-top: 2px solid var(--ink); }
      .nav-mobile.open { display: flex; }
      .nav-mobile a { padding: 14px 0; font-size: 16px; border-bottom: 1px solid var(--line-soft); }
      .nav-mobile a.nav-mobile-sub { padding: 11px 0 11px 18px; font-size: 14px; color: var(--ink-soft); }
    }

    .crumb { padding: 20px 0; font-family: var(--font-mono); font-size: 12.5px; color: var(--ink-soft); border-bottom: 1px solid var(--line-soft); }
    .crumb a { color: var(--ink-soft); }
    .crumb a:hover { color: var(--orange); }
    .crumb .sep { margin: 0 8px; }
    .crumb .current { color: var(--ink); }

    .art-head { padding: 46px 0 36px; border-bottom: 2px solid var(--ink); }
    .art-tag { display: inline-block; border: 1px solid var(--orange); color: var(--orange); font-family: var(--font-mono); font-size: 11.5px; font-weight: 700; padding: 3px 10px; letter-spacing: 1px; margin-bottom: 18px; }
    .art-head h1 { font-family: var(--font-display); font-weight: 900; font-size: clamp(28px, 4.4vw, 42px); line-height: 1.3; }
    .art-meta { display: flex; gap: 18px; flex-wrap: wrap; margin-top: 18px; font-family: var(--font-mono); font-size: 12.5px; color: var(--ink-soft); }

    .art-body { padding: 44px 0 20px; }
    .art-body p { color: var(--ink-soft); margin-bottom: 18px; font-size: 15.5px; }
    .art-body h2 { font-family: var(--font-display); font-weight: 900; font-size: 24px; margin: 42px 0 16px; }
    .art-body h2 .idx { font-family: var(--font-mono); color: var(--orange); margin-right: 8px; }
    .art-body h3 { font-family: var(--font-display); font-weight: 900; font-size: 18px; margin: 26px 0 12px; }
    .art-body strong { color: var(--ink); }
    .art-body ul.bullets { margin: 0 0 18px; }
    .art-body ul.bullets li { position: relative; padding-left: 20px; color: var(--ink-soft); font-size: 15px; margin-bottom: 8px; }
    .art-body ul.bullets li::before { content: "—"; position: absolute; left: 0; color: var(--orange); }
    .inline-code { font-family: var(--font-mono); font-size: 0.88em; background: var(--paper-2); border: 1px solid var(--line-soft); padding: 1px 6px; }

    .code-box { background: var(--ink); color: #e8e2d4; border: 2px solid var(--ink); font-family: var(--font-mono); font-size: 13px; line-height: 1.85; padding: 20px 24px; margin: 10px 0 26px; overflow-x: auto; }
    .code-box .k { color: #7fd8ff; }
    .code-box .s { color: #ffb38a; }
    .code-box .c { color: #6f6a5e; }

    .doc-table-wrap { border: 2px solid var(--ink); overflow-x: auto; margin: 6px 0 26px; }
    table.doc-table { width: 100%; border-collapse: collapse; font-size: 13.5px; min-width: 560px; }
    table.doc-table th { font-family: var(--font-mono); font-size: 11.5px; letter-spacing: 1px; text-transform: uppercase; text-align: left; color: var(--ink-soft); padding: 12px 16px; border-bottom: 2px solid var(--ink); background: var(--paper-2); }
    table.doc-table td { padding: 12px 16px; border-bottom: 1px solid var(--line-soft); vertical-align: top; color: var(--ink-soft); }
    table.doc-table tr:last-child td { border-bottom: none; }
    table.doc-table td.code { font-family: var(--font-mono); font-size: 12.5px; color: var(--orange-dark); white-space: nowrap; }

    .tip-line { font-size: 14px; color: var(--ink-soft); border-left: 3px solid var(--orange); padding: 4px 0 4px 16px; margin: 20px 0 26px; }
    .tip-line b { color: var(--ink); }

    .related-sec { border-top: 2px solid var(--ink); padding: 48px 0; background: var(--paper-2); }
    .related-sec .wide > .label { font-family: var(--font-mono); font-size: 12px; letter-spacing: 2px; color: var(--ink-soft); text-transform: uppercase; margin-bottom: 20px; display: block; }
    .related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
    .related-card { border: 2px solid var(--ink); background: var(--paper); padding: 22px; transition: transform .2s, box-shadow .2s; }
    .related-card:hover { transform: translateY(-3px); box-shadow: 5px 5px 0 var(--orange); }
    .related-card b { display: block; font-family: var(--font-display); font-size: 15.5px; font-weight: 900; margin-bottom: 6px; }
    .related-card span { font-size: 12.5px; color: var(--ink-soft); font-family: var(--font-mono); }

    .doc-cta { display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; border: 2px solid var(--ink); background: var(--paper); padding: 26px 30px; margin-top: 30px; }
    .doc-cta b { font-family: var(--font-display); font-size: 17px; font-weight: 900; display: block; margin-bottom: 4px; }
    .doc-cta span { font-size: 13.5px; color: var(--ink-soft); }
    .btn { display: inline-flex; align-items: center; gap: 10px; font-size: 14.5px; font-weight: 700; padding: 12px 24px; border: 2px solid var(--ink); cursor: pointer; transition: transform .15s, box-shadow .15s; }
    .btn:hover { transform: translate(-3px, -3px); box-shadow: 5px 5px 0 var(--ink); }
    .btn-primary { background: var(--orange); color: var(--paper); }

    /* ============ Floating download CTA ============ */
    .float-dl { position: fixed; right: 22px; bottom: 22px; z-index: 200; animation: float-dl-in .4s cubic-bezier(.22,1,.36,1); }
    .float-dl.hide { display: none; }
    .float-dl-inner { position: relative; }
    .float-dl-btn {
      display: inline-flex; align-items: center; gap: 9px;
      background: var(--orange); color: var(--paper);
      border: 2px solid var(--ink);
      padding: 13px 20px;
      font-size: 14px; font-weight: 700;
      box-shadow: 4px 4px 0 var(--ink);
      transition: transform .15s, box-shadow .15s;
    }
    .float-dl-btn:hover { transform: translate(-2px, -2px); box-shadow: 6px 6px 0 var(--ink); }
    .float-dl-btn svg { width: 16px; height: 16px; flex-shrink: 0; }
    .float-dl-close {
      position: absolute; top: -10px; right: -10px;
      width: 21px; height: 21px;
      background: var(--ink); color: var(--paper);
      border: 2px solid var(--paper); border-radius: 50%;
      font-size: 12px; line-height: 1; cursor: pointer;
      display: flex; align-items: center; justify-content: center;
      padding: 0;
    }
    @keyframes float-dl-in { from { opacity: 0; transform: translateY(18px); } to { opacity: 1; transform: none; } }
    @media (max-width: 480px) {
      .float-dl { right: 14px; bottom: 14px; }
      .float-dl-btn span { display: none; }
      .float-dl-btn { padding: 14px; border-radius: 50%; }
    }
    @media (prefers-reduced-motion: reduce) {
      .float-dl { animation: none; }
    }

    footer { background: var(--paper-2); }
    .foot-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.3fr; gap: 44px; padding: 56px 0 44px; border-bottom: 1px solid var(--line-soft); }
    .foot-grid h4 { font-family: var(--font-mono); font-size: 12px; letter-spacing: 2px; color: var(--ink-soft); margin-bottom: 18px; text-transform: uppercase; }
    .foot-grid ul li { margin-bottom: 10px; }
    .foot-grid a { font-size: 14.5px; border-bottom: 1px solid transparent; transition: border-color .15s, color .15s; }
    .foot-grid a:hover { color: var(--orange); border-bottom-color: var(--orange); }
    .foot-brand .logo { border-right: none; padding-right: 0; }
    .foot-brand p { color: var(--ink-soft); font-size: 14px; margin-top: 16px; max-width: 300px; }
    .foot-lang { display: flex; flex-wrap: wrap; gap: 8px; }
    .foot-lang a { font-size: 12.5px; font-family: var(--font-mono); border: 1.5px solid var(--line-soft); padding: 5px 12px; cursor: pointer; transition: all .15s; display: inline-block; text-decoration: none; color: inherit; }
    .foot-lang a:hover { border-color: var(--ink); }
    .foot-lang a.current { background: var(--ink); color: var(--paper); border-color: var(--ink); }
    .foot-bottom { padding: 24px 0 30px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; font-size: 13px; color: var(--ink-soft); }

    @media (max-width: 720px) {
      .related-grid { grid-template-columns: 1fr; }
      .foot-grid { grid-template-columns: 1fr 1fr; }
      .doc-cta { flex-direction: column; align-items: flex-start; }
      .doc-table-wrap::before,
      .code-box::before {
        content: "← 可左右滑动 →";
        display: inline-block;
        position: sticky;
        left: 0;
        font-family: var(--font-mono);
        font-size: 10px;
        letter-spacing: .3px;
        color: var(--ink-soft);
        background: var(--paper-2);
        border: 1px solid var(--line-soft);
        padding: 3px 9px;
        margin: 8px 0 8px 8px;
      }
      .code-box::before { background: rgba(232, 226, 212, 0.12); color: rgba(232, 226, 212, 0.6); border-color: rgba(232, 226, 212, 0.2); margin: 0 0 10px; }
      html[lang="en"] .doc-table-wrap::before, html[lang="en"] .code-box::before { content: "← Scroll →"; }
      html[lang="ja"] .doc-table-wrap::before, html[lang="ja"] .code-box::before { content: "← 左右にスクロール →"; }
      html[lang="ko"] .doc-table-wrap::before, html[lang="ko"] .code-box::before { content: "← 좌우로 스크롤 →"; }
      html[lang="zh-TW"] .doc-table-wrap::before, html[lang="zh-TW"] .code-box::before { content: "← 可左右滑動 →"; }
    }
    @media (prefers-reduced-motion: reduce) {
      .ticker-track { animation: none; }
      html { scroll-behavior: auto; }
    }