/* --------------------------------------------------
       Global Settings
    -------------------------------------------------- */
    :root {
      --primary: #0ea5e9;
      --primary-dark: #0284c7;
      --bg: #f8fafc;
      --card: #ffffff;
      --text: #1e293b;
      --text-muted: #64748b;
      --border: #e2e8f0;
      --accent-bg: #f1f5f9;
      --shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
      --radius: 12px;
      --max-width: 1000px;
    }

    * { box-sizing: border-box; }

    body {
      margin: 0;
      font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
      color: var(--text);
      background-color: var(--bg);
      line-height: 1.7;
      word-break: break-all;
    }

    a { color: var(--primary); text-decoration: none; transition: 0.2s; }
    a:hover { color: var(--primary-dark); }

    img { max-width: 100%; height: auto; display: block; }

    /* --------------------------------------------------
       Layout Components
    -------------------------------------------------- */
    header {
      background: var(--card);
      border-bottom: 1px solid var(--border);
      position: sticky;
      top: 0;
      z-index: 100;
    }

    .header-inner {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 12px 16px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .brand strong { font-size: 1.1rem; color: var(--text); display: block; }
    .brand span { font-size: 0.75rem; color: var(--text-muted); }

    nav { display: flex; gap: 16px; }
    nav a { font-size: 0.85rem; font-weight: 600; color: var(--text-muted); }
    nav a:hover { color: var(--primary); }

    @media (max-width: 640px) {
      nav { display: none; }
    }

    .breadcrumb {
      max-width: var(--max-width);
      margin: 12px auto;
      padding: 0 16px;
      font-size: 0.8rem;
      color: var(--text-muted);
    }

    .wrap {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 16px 60px;
    }

    /* --------------------------------------------------
       Main Card Style
    -------------------------------------------------- */
    .main-card {
      background: var(--card);
      border-radius: var(--radius);
      border: 1px solid var(--border);
      box-shadow: var(--shadow);
      overflow: hidden;
    }

    .hero {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
      padding: 32px;
      background: linear-gradient(to bottom right, #fff, var(--bg));
      align-items: center;
      border-bottom: 1px solid var(--border);
    }

    @media (max-width: 768px) {
      .hero { grid-template-columns: 1fr; gap: 24px; padding: 24px; }
    }

    .hero-content h1 { margin: 12px 0; font-size: 1.6rem; line-height: 1.3; }
    .badge {
      display: inline-block;
      background: var(--primary);
      color: #fff;
      font-size: 0.7rem;
      font-weight: bold;
      padding: 2px 8px;
      border-radius: 4px;
      text-transform: uppercase;
    }

    .lead { font-size: 0.95rem; color: var(--text); }

    .hero-image img {
      border-radius: var(--radius);
      box-shadow: var(--shadow);
      border: 1px solid var(--border);
    }

    .article-body { padding: 32px; }
    @media (max-width: 640px) { .article-body { padding: 20px; } }

    /* --------------------------------------------------
       Typography & UI Elements
    -------------------------------------------------- */
    h2 {
      font-size: 1.3rem;
      border-left: 4px solid var(--primary);
      padding-left: 12px;
      margin: 40px 0 20px;
      color: var(--text);
    }

    .toc {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin: 20px 0;
    }

    .toc a {
      font-size: 0.8rem;
      background: var(--accent-bg);
      color: var(--text);
      padding: 6px 14px;
      border-radius: 20px;
      border: 1px solid var(--border);
    }

    .toc a:hover { background: var(--primary); color: #fff; border-color: var(--primary); }

    /* Tables */
    .table-responsive { overflow-x: auto; margin: 20px 0; }
    table {
      width: 100%;
      border-collapse: collapse;
      font-size: 0.9rem;
      border: 1px solid var(--border);
    }

    th, td { padding: 12px 16px; border-bottom: 1px solid var(--border); text-align: left; }
    th { background: var(--accent-bg); color: var(--text-muted); font-weight: 600; width: 30%; }

    /* Price Section */
    .price-card-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 20px;
      margin: 20px 0;
    }

    .price-item {
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 16px;
      background: #fff;
    }

    .price-item h3 { margin: 0 0 12px; font-size: 1rem; color: var(--primary); }
    .price-amount { font-size: 1.5rem; font-weight: 800; }
    .price-unit { font-size: 0.8rem; color: var(--text-muted); }

    .btn {
      display: block;
      width: 100%;
      background: var(--primary);
      color: #fff;
      text-align: center;
      padding: 10px;
      border-radius: 8px;
      font-weight: bold;
      border: none;
      cursor: pointer;
      margin-top: 12px;
      transition: 0.2s;
    }

    .btn:hover { background: var(--primary-dark); }

    /* FAQ */
    .faq-container { border: 1px solid var(--border); border-radius: var(--radius); margin-top: 20px; }
    .faq-item { border-bottom: 1px solid var(--border); }
    .faq-item:last-child { border-bottom: none; }
    .faq-q {
      width: 100%;
      padding: 16px;
      background: none;
      border: none;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
      font-size: 0.9rem;
      text-align: left;
    }

    .faq-a {
      padding: 0 16px 16px;
      font-size: 0.9rem;
      color: var(--text-muted);
      display: none;
    }
    .faq-a.is-open { display: block; }

    /* Related Products */
    .related-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
      gap: 16px;
      margin-top: 20px;
    }

    .related-item {
      text-align: center;
      font-size: 0.8rem;
    }

    .related-item img {
      border: 1px solid var(--border);
      border-radius: 8px;
      margin-bottom: 8px;
    }

    .related-name { font-weight: bold; display: block; color: var(--text); }
    .related-price { color: var(--text-muted); }

    /* Footer */
    footer {
      background: #27272a;
      color: #e2e8f0;
      padding: 60px 16px;
      text-align: center;
    }

    .footer-logo { font-size: 1.4rem; font-weight: bold; margin-bottom: 24px; display: block; color: #fff; }
    .footer-nav {
      display: flex;
      justify-content: center;
      flex-wrap: wrap;
      gap: 24px;
      margin-bottom: 32px;
      padding: 0;
      list-style: none;
    }

    .footer-nav a { color: #94a3b8; font-size: 0.85rem; }
    .footer-nav a:hover { color: #fff; }
    .copyright { font-size: 0.75rem; color: #64748b; }

    /* Toast */
    .toast {
      position: fixed;
      bottom: 24px;
      left: 50%;
      transform: translateX(-50%);
      background: #1e293b;
      color: #fff;
      padding: 12px 24px;
      border-radius: 40px;
      font-size: 0.85rem;
      box-shadow: 0 10px 15px -3px rgba(0,0,0,0.1);
      display: none;
      z-index: 1000;
    }
    .toast.show { display: block; animation: fadeIn 0.3s; }

    @keyframes fadeIn { from { opacity: 0; bottom: 10px; } to { opacity: 1; bottom: 24px; } }