*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
    :root {
      --primary: #4CAF50;
      --primary-dark: #388E3C;
      --primary-light: #C8E6C9;
      --bg: #FAFAF5;
      --surface: #FFFFFF;
      --text: #1A2E20;
      --text-sub: #5F7A65;
    }
    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: var(--bg);
      color: var(--text);
      line-height: 1.7;
    }
    /* NAV */
    nav {
      padding: 16px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-bottom: 1px solid rgba(0,0,0,0.06);
      background: rgba(250,250,245,0.95);
      backdrop-filter: blur(16px);
      position: sticky;
      top: 0;
      z-index: 100;
    }
    .nav-logo {
      font-family: 'Pacifico', cursive;
      font-size: 1.6rem;
      color: var(--primary);
      text-decoration: none;
    }
    nav a.back-link {
      color: var(--text-sub);
      text-decoration: none;
      font-size: 0.9rem;
      font-weight: 600;
    }
    nav a.back-link:hover { color: var(--primary); }

    /* LINE / in-app WebView: backdrop-filter can blank the compositor layer */
    @media (max-width: 1024px), (hover: none) and (pointer: coarse) {
      nav {
        backdrop-filter: none;
        -webkit-backdrop-filter: none;
        background: rgba(250, 250, 245, 0.98);
      }
    }

    /* HEADER */
    .page-header {
      background: linear-gradient(135deg, #2E7D32 0%, #4CAF50 40%, #66BB6A 100%);
      color: white;
      text-align: center;
      padding: 60px 24px 48px;
    }
    .page-header h1 {
      font-size: 2rem;
      font-weight: 800;
      margin-bottom: 8px;
    }
    .page-header p {
      opacity: 0.85;
      font-size: 0.95rem;
    }

    /* CONTENT */
    main {
      max-width: 800px;
      margin: -24px auto 60px;
      padding: 40px 32px;
      background: var(--surface);
      border-radius: 20px;
      box-shadow: 0 8px 24px rgba(0,0,0,0.08);
      position: relative;
      z-index: 2;
    }
    h2 {
      color: var(--primary-dark);
      font-size: 1.2rem;
      font-weight: 700;
      margin-top: 32px;
      margin-bottom: 12px;
      padding-bottom: 8px;
      border-bottom: 2px solid rgba(76,175,80,0.2);
    }
    h2:first-of-type { margin-top: 0; }
    h3 {
      font-size: 1.05rem;
      font-weight: 700;
      margin-top: 24px;
      margin-bottom: 8px;
    }
    p { margin-bottom: 12px; }
    ul { margin: 8px 0 16px 20px; }
    li { margin-bottom: 8px; font-size: 0.95rem; color: var(--text-sub); line-height: 1.6; }
    li strong { color: var(--text); }
    a { color: var(--primary-dark); text-decoration: none; }
    a:hover { text-decoration: underline; }
    .updated {
      display: inline-block;
      background: rgba(76,175,80,0.1);
      color: var(--primary-dark);
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 600;
      margin-bottom: 24px;
    }
    .contact-box {
      background: var(--bg);
      padding: 20px 24px;
      border-radius: 16px;
      margin-top: 24px;
      border: 1px solid rgba(0,0,0,0.06);
    }
    .related-link {
      display: inline-block;
      margin-top: 24px;
      padding: 10px 20px;
      background: rgba(76,175,80,0.1);
      border-radius: 12px;
      font-weight: 600;
      font-size: 0.9rem;
    }

    /* LANG TOGGLE */
    [data-lang="en"] [data-ja],
    [data-lang="ja"] [data-en] { display: none !important; }
    .lang-switcher {
      text-align: right;
      margin-bottom: 24px;
    }
    .lang-toggle {
      background: var(--primary-light);
      color: var(--primary-dark);
      border: 1px solid var(--primary);
      padding: 6px 16px;
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 700;
      cursor: pointer;
      transition: all 0.2s;
    }
    .lang-toggle:hover { background: var(--primary); color: white; }

    /* FOOTER */
    footer {
      text-align: center;
      padding: 32px 24px;
      border-top: 1px solid rgba(0,0,0,0.06);
    }
    .footer-logo {
      font-family: 'Pacifico', cursive;
      font-size: 1.4rem;
      color: var(--primary);
      margin-bottom: 4px;
    }
    .footer-links {
      display: flex;
      gap: 24px;
      justify-content: center;
      margin: 12px 0;
      flex-wrap: wrap;
    }
    .footer-links a {
      color: var(--text-sub);
      text-decoration: none;
      font-size: 0.88rem;
    }
    .footer-links a:hover { color: var(--primary); }
    footer p { color: var(--text-sub); font-size: 0.8rem; }

    @media (max-width: 600px) {
      main { margin: -16px 12px 40px; padding: 28px 20px; }
    }