:root {
      --accent: #2563eb;
      --accent-soft: #e8f0ff;
      --border: #dbe2ea;
      --sidebar-width: 18rem;
      --text: #1e293b;
    }

    * { box-sizing: border-box; }

    html {
      scroll-behavior: smooth;
      scroll-padding-top: 2rem;
    }

    body {
      margin: 0;
      color: var(--text);
      background: #f8fafc;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN",
        "Hiragino Sans", "Yu Gothic UI", Meiryo, sans-serif;
      font-size: 16px;
      line-height: 1.8;
    }

    a {
      color: #1d4ed8;
      text-underline-offset: 0.18em;
    }

    a:hover { color: #1e40af; }

    .sidebar {
      position: fixed;
      z-index: 20;
      inset: 0 auto 0 0;
      display: flex;
      width: var(--sidebar-width);
      flex-direction: column;
      padding: 1.5rem 1rem;
      overflow-y: auto;
      border-right: 1px solid var(--border);
      background: #fff;
    }

    .sidebar-header {
      padding: 0 0.65rem 1rem;
      border-bottom: 1px solid var(--border);
    }

    .sidebar-label {
      margin: 0 0 0.15rem;
      color: var(--accent);
      font-size: 0.72rem;
      font-weight: 700;
      letter-spacing: 0.12em;
      text-transform: uppercase;
    }

    .sidebar-title {
      margin: 0;
      font-size: 1.05rem;
      line-height: 1.45;
    }

    #toc { padding-top: 0.85rem; }

    #toc ul {
      margin: 0;
      padding: 0;
      list-style: none;
    }

    #toc ul ul {
      margin: 0.2rem 0 0.35rem 0.85rem;
      padding-left: 0.7rem;
      border-left: 1px solid var(--border);
    }

    #toc a {
      display: block;
      margin: 0.1rem 0;
      padding: 0.42rem 0.65rem;
      border-radius: 0.45rem;
      color: #475569;
      font-size: 0.9rem;
      line-height: 1.45;
      text-decoration: none;
      transition: color 150ms ease, background-color 150ms ease;
    }

    #toc ul ul a { font-size: 0.84rem; }

    #toc a:hover {
      color: #1d4ed8;
      background: #f1f5f9;
    }

    #toc a.is-active {
      color: #1d4ed8;
      background: var(--accent-soft);
      font-weight: 700;
    }

    .content {
      min-height: 100vh;
      margin-left: var(--sidebar-width);
      padding: 3.5rem clamp(1.5rem, 5vw, 5rem) 6rem;
    }

    .markdown-body {
      width: min(100%, 58rem);
      margin: 0 auto;
      padding: clamp(1.75rem, 4vw, 3.5rem);
      border: 1px solid var(--border);
      border-radius: 0.85rem;
      background: #fff;
      box-shadow: 0 12px 35px rgb(15 23 42 / 7%);
    }

    .markdown-body > :first-child { margin-top: 0; }
    .markdown-body > :last-child { margin-bottom: 0; }

    .markdown-body h1,
    .markdown-body h2,
    .markdown-body h3 {
      color: #0f172a;
      line-height: 1.35;
      scroll-margin-top: 2rem;
    }

    .markdown-body h1 {
      margin-bottom: 2.25rem;
      padding-bottom: 0.8rem;
      border-bottom: 2px solid var(--accent);
      font-size: clamp(1.9rem, 4vw, 2.65rem);
    }

    .markdown-body h2 {
      margin: 3rem 0 1.25rem;
      padding-bottom: 0.45rem;
      border-bottom: 1px solid var(--border);
      font-size: clamp(1.4rem, 3vw, 1.8rem);
    }

    .markdown-body h3 {
      margin: 2.1rem 0 0.9rem;
      font-size: 1.25rem;
    }

    .markdown-body p,
    .markdown-body ul,
    .markdown-body ol { margin: 0 0 1.3rem; }

    .markdown-body img {
      display: block;
      max-width: 100%;
      height: auto;
      margin: 1.5rem auto 2rem;
      border: 1px solid var(--border);
      border-radius: 0.6rem;
      box-shadow: 0 8px 24px rgb(15 23 42 / 10%);
    }

    .markdown-body p img[height] {
      display: inline-block;
      width: auto;
      margin: 0 0.15em;
      border: 0;
      border-radius: 0;
      box-shadow: none;
      vertical-align: -0.08em;
    }

    .markdown-body pre {
      margin: 1.5rem 0 2rem;
      overflow-x: auto;
      border: 1px solid #30363d;
      border-radius: 0.6rem;
      background: #0d1117;
      box-shadow: 0 8px 24px rgb(15 23 42 / 16%);
    }

    .markdown-body pre code.hljs {
      display: block;
      padding: 1.25rem 1.4rem;
      color: #c9d1d9;
      background: #0d1117;
      font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
      font-size: 0.92rem;
      line-height: 1.65;
      tab-size: 2;
    }

    .markdown-body .code-block {
      margin: 1.5rem 0 2rem;
      overflow: hidden;
      border: 1px solid #30363d;
      border-radius: 0.6rem;
      background: #0d1117;
      box-shadow: 0 8px 24px rgb(15 23 42 / 16%);
    }

    .markdown-body .code-block__filename {
      padding: 0.5rem 1rem;
      border-bottom: 1px solid #30363d;
      color: #e6edf3;
      background: #161b22;
      font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
      font-size: 0.82rem;
      font-weight: 600;
      line-height: 1.5;
    }

    .markdown-body .code-block pre {
      margin: 0;
      border: 0;
      border-radius: 0;
      box-shadow: none;
    }

    .legacy-anchor {
      position: relative;
      top: -2rem;
    }

    .menu-toggle {
      position: fixed;
      z-index: 40;
      top: 0.8rem;
      left: 0.8rem;
      display: none;
      align-items: center;
      justify-content: center;
      width: 2.75rem;
      height: 2.75rem;
      padding: 0;
      border: 1px solid var(--border);
      border-radius: 0.65rem;
      color: #0f172a;
      background: #fff;
      box-shadow: 0 4px 14px rgb(15 23 42 / 12%);
      cursor: pointer;
      font: inherit;
      font-size: 1.35rem;
    }

    .menu-overlay {
      position: fixed;
      z-index: 10;
      inset: 0;
      display: none;
      background: rgb(15 23 42 / 45%);
    }

    @media (max-width: 860px) {
      .sidebar {
        z-index: 30;
        width: min(85vw, var(--sidebar-width));
        transform: translateX(-105%);
        box-shadow: 12px 0 30px rgb(15 23 42 / 18%);
        transition: transform 180ms ease;
      }

      .sidebar.is-open { transform: translateX(0); }
      .menu-toggle { display: flex; }
      .menu-overlay.is-visible { display: block; }

      .content {
        margin-left: 0;
        padding: 4.5rem 1rem 3rem;
      }

      .markdown-body { padding: 1.5rem; }
    }

    @media (prefers-reduced-motion: reduce) {
      html { scroll-behavior: auto; }
      .sidebar, #toc a { transition: none; }
    }

    @media print {
      .sidebar, .menu-toggle, .menu-overlay { display: none; }

      .content {
        margin: 0;
        padding: 0;
      }

      .markdown-body {
        width: 100%;
        padding: 0;
        border: 0;
        box-shadow: none;
      }
    }
  
    .lead { color: #52606d; }
    .small { font-size: .85rem; color: #52606d; }
    .notice { padding: 1rem 1.2rem; margin: 1.5rem 0; border-left: 4px solid var(--accent); background: var(--accent-soft); }
    .route-links { display: flex; flex-wrap: wrap; gap: .6rem; margin: 1.5rem 0; }
    .route-links a { border: 1px solid var(--border); border-radius: .45rem; padding: .6rem .9rem; font-weight: 600; background: #f8fafc; }
    .markdown-body table { width: 100%; border-collapse: collapse; margin: 1.5rem 0; font-size: .93rem; }
    .markdown-body th, .markdown-body td { border-bottom: 1px solid var(--border); padding: .7rem .8rem; text-align: left; vertical-align: top; overflow-wrap: anywhere; }
    .markdown-body th { background: #f1f5f9; }
    .markdown-body code { font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace; }
    .markdown-body :not(pre) > code { padding: .12rem .3rem; border-radius: .25rem; background: #f1f5f9; font-size: .9em; overflow-wrap: anywhere; }
    .markdown-body pre code { white-space: pre; }
    .markdown-body .code-block { margin-left: 0; margin-right: 0; }
    .markdown-body li + li { margin-top: .35rem; }
    .checklist { padding-left: 0; list-style: none; }
    .checklist label { display: block; cursor: pointer; }
    .checklist input { accent-color: var(--accent); width: 1rem; height: 1rem; margin-right: .5rem; }
    a:focus-visible, button:focus-visible, input:focus-visible { outline: 3px solid #2563eb; outline-offset: 3px; }
    .sidebar-back { display: block; margin-top: .65rem; font-size: .8rem; }
    @media (max-width: 860px) { html { scroll-padding-top: 5rem; } .markdown-body h2, .markdown-body h3 { scroll-margin-top: 5rem; } }
    @media (max-width: 520px) { .markdown-body { padding: 1.15rem; } .markdown-body th, .markdown-body td { padding: .5rem .35rem; font-size: .85rem; } }
    @media print { .route-links { display: none; } .markdown-body pre { white-space: pre-wrap; } .markdown-body pre code.hljs { color: #111; background: #fff; white-space: pre-wrap; overflow-wrap: anywhere; } .markdown-body h2, .markdown-body h3 { break-after: avoid; } .markdown-body img, .code-block, tr { break-inside: avoid; } }