body {
    margin: 0;
    font-family: Arial, sans-serif;
    background: #fff;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    padding-top: 0;
  }

  .logo {
    position: static;
    top: auto;
    background: #fff; /* 背景色を指定し重なり防止 */
    padding: 0.5rem;
    text-align: left;
  }

  .logo img {
    display: block;
    max-width: 300px;
    height: auto;
  }

  header.navbar {
    position: static;
    top: auto; /* ロゴの高さ分ずらす */
  }

  /* メニューバーのスタイル */
  .navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: #f5f6f7;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    z-index: 1000;
  }

  .nav-container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0.6rem 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
  }

  .nav-logo {
    color: white;
    font-weight: bold;
    font-size: 1.2rem;
    text-decoration: none;
  }

  .nav-menu {
    list-style: none;
    display: flex;
    gap: 1rem;
    margin: 0;
    padding: 0;
  }

  .nav-menu li a {
    color: #000000;
    text-decoration: none;
    font-weight: 500;
    padding: 0.3rem 0.6rem;
    border-radius: 3px;
    transition: background-color 0.3s;
  }

  .nav-menu li a:hover {
    background-color: rgba(255,255,255,0.3);
  }

  .footer {
    width: 100%;
    background-color: #f5f6f7;
    color: #000000;
    padding: 0.3rem 0;
    margin-top: 2rem;
    text-align: center;
  }

  /* パンくず */
  .breadcrumb {
    font-size: 0.85rem;
    margin: 10px 20px;
  }

  .breadcrumb a {
    color: #004080;
    text-decoration: none;
  }

  /* タイトル */
  .page-title {
    text-align: center;
    margin: 20px 0;
    font-size: 1.6rem;
  }

  /* 詳細エリア */
  .detail-container {
    display: flex;
    gap: 20px;
    min-width: 1000px;
    max-width: 1200px;
    margin: 0 auto;
    background: #fff;
    padding: 20px;
    border-radius: 6px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  }

  .detail-image img {
    width: 200px;
    height: auto;
    border: 1px solid #ccc;
  }

  .detail-info {
    flex: 1;
  }

  .book-title {
    font-size: 1.4rem;
    margin-bottom: 10px;
  }

  .info-table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 15px;
  }

  .info-table th {
    text-align: left;
    width: 150px;
    padding: 5px;
    background: #f0f0f0;
    font-weight: normal;
  }

  .info-table td {
    padding: 5px;
  }

  .action-buttons {
    display: flex;
    gap: 10px;
  }

  .btn-primary {
    background: #004080;
    color: #fff;
    border: none;
    padding: 10px 15px;
    cursor: pointer;
    border-radius: 4px;
  }

  .btn-secondary {
    background: #ccc;
    border: none;
    padding: 10px 15px;
    cursor: pointer;
    border-radius: 4px;
  }

  .detail-table-section {
    max-width: 1200px;
    min-width: 1000px;
    margin: 20px auto;
    background: #fff;
    padding: 20px;
    border-radius: 6px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
    margin-top: 1rem;
  }

  .detail-table-section.hidden {
    display: none;
  }

  .detail-toggle {
    max-width: 1200px;  /* detail-table-section と同じ幅 */
    min-width: 1000px;
    margin: 10px auto 0 auto; /* 上マージンだけ少し */
  }

  .detail-toggle a {
    color: #007BFF;
    text-decoration: underline;
    cursor: pointer;
  }

  .detail-toggle a:hover {
   color: #004080;
  } 


  .detail-table-section .info-table th {
    width: 220px;
    min-width: 150px;
    background: #f0f0f0;
    text-align: left;
    padding: 8px;
  }

  .detail-table-section .info-table td {
    padding: 8px;
  }

  .holding-list-section {
    max-width: 1200px;
    min-width: 1000px;
    margin: 20px auto;
    background: #fff;
    padding: 20px;
    border-radius: 6px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  }

  .holding-list-section h3 {
    margin-bottom: 15px;
    font-size: 1.2rem;
    color: #004080;
  }

  .holding-list li {
    display: flex;
    gap: 20px;
    padding: 10px 0;
    border-bottom: 1px solid #eee;
  }

  .holding-list li {
    padding: 10px 0;
    border-bottom: 1px solid #eee;
    font-size: 0.95rem;
    display: flex;
    gap: 20px;
  }

  .holding-list li span {
    min-width: 150px;
  }

  .holding-status {
    font-weight: bold;
    color: #007BFF; /* 貸出可能は青色 */
  }

  .holding-no {
    min-width: 40px !important;
    flex: 0 0 40px;
    text-align: right;
  }

  /* ヘッダー行 */
  .holding-header {
    font-weight: bold;
    background: #f0f0f0;
    border-bottom: 2px solid #ccc;
  }

  /* レスポンシブ */
  @media (max-width: 768px) {
    .detail-container {
      flex-direction: column;
      align-items: center;
    }
    .detail-image img {
      max-width: 100%;
    }
  }

  .external-links-section {
    max-width: 1200px;
    min-width: 1000px;
    margin: 20px auto;
    background: #fff;
    padding: 20px;
    border-radius: 6px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
  }

  .external-links-section h3 {
    font-size: 1.2rem;
    color: #004080;
    margin-bottom: 15px;
  }

  .external-links-list {
    display: flex;
    gap: 15px; /* リンク間の間隔 */
  }

  .external-links-list a {
    color: #007BFF;
    text-decoration: underline;
    padding: 6px 12px;
    border-radius: 4px;
    border: 1px solid #007BFF;
    transition: all 0.2s;
  }

  .external-links-list a:hover {
    background-color: #007BFF;
    color: #fff;
    text-decoration: none;
  }

  .detail-nav-links {
    max-width: 1200px;
    min-width: 1000px;
    margin: 20px auto 20px auto; /* navbar の下に余白を確保 */
    display: flex;
    align-items: center;
    gap: 20px;
    font-size: 0.95rem;
    justify-content: flex-end;
  }

  .detail-nav-links a {
    color: #007BFF;
    text-decoration: underline;
    cursor: pointer;
  }

  .detail-nav-links a:hover {
   color: #004080;
  } 

.detail-nav-links .current-info {
  font-weight: bold;
}