/* h2要素の装飾 */
h2 {
  color: #1a1a1a;
  font-weight: 700;
  font-size: 2.2rem;
  text-align: center;
  margin: 3rem 0 2rem 0;
  padding: 1.5rem 2rem;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  border-radius: 15px;
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  position: relative;
  overflow: hidden;
}

h2::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  animation: shine 3s infinite;
}

@keyframes shine {
  0% { left: -100%; }
  50% { left: 100%; }
  100% { left: 100%; }
}

/* PCサイズ（768px以上）でのみハンバーガーメニューを強制表示 */
@media (min-width: 768px) {
  .navbar-collapse:not(.show) {
    display: none !important;
  }
  
  .navbar-collapse.show {
    display: block !important;
    position: absolute !important;
    top: 100% !important;
    left: 0 !important;
    right: 0 !important;
    background-color: #343a40 !important;
    z-index: 1000 !important;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1) !important;
  }
  
  .navbar-toggler {
    display: block !important;
    visibility: visible !important;
    opacity: 1 !important;
    position: relative !important;
    z-index: 1001 !important;
  }
  
  .navbar-nav {
    margin-top: 0 !important;
    flex-direction: column !important;
    width: 100% !important;
  }
  
  .navbar-nav .nav-link {
    padding: 0.75rem 1rem !important;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1) !important;
    width: 100% !important;
  }
  
  .navbar-nav .nav-link:last-child {
    border-bottom: none !important;
  }
  
  /* ネット予約ボタンの横幅調整 */
  .navbar-nav .nav-link.btn {
    width: 50vw !important;
    display: block !important;
    margin: 0.5rem auto !important;
    text-align: center !important;
  }
  
  /* アニメーションをスムーズに */
  .navbar-collapse {
    transition: all 0.3s ease-in-out !important;
  }
  
  .navbar {
    position: relative !important;
  }
}

/* 目次のスタイル */
.toc-container {
  background-color: #f8f9fa;
  border: 1px solid #dee2e6;
  border-radius: 8px;
  padding: 1.5rem;
}

.toc-header {
  display: flex;
  align-items: center;
}

.toc-header h3 {
  margin: 0;
  color: #495057;
  font-size: 1.3rem;
}

.toc-header i {
  color: #6c757d;
  transition: transform 0.3s ease;
}

.accordion-header .btn-link {
  color: #495057;
  text-decoration: none;
  font-weight: 600;
  padding: 0.75rem 1rem;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}

.accordion-header .btn-link:hover {
  color: #007bff;
  background-color: #e9ecef;
  border-radius: 4px;
}

.accordion-header .btn-link:focus {
  box-shadow: none;
  outline: none;
}

.toc-h2 {
  color: #2c3e50;
  font-weight: 600;
  text-decoration: none;
  display: block;
  padding: 0.5rem 0;
  border-bottom: 1px solid #e9ecef;
}

.toc-h5 {
  color: #6c757d;
  text-decoration: none;
  display: block;
  padding: 0.3rem 0;
  font-size: 0.9rem;
}

.toc-sub-list {
  margin-top: 0.5rem;
  margin-bottom: 0.5rem;
}

.toc-h2:hover,
.toc-h5:hover {
  color: #007bff;
  text-decoration: underline;
}

/* レスポンシブiframe */
iframe {
  max-width: 100%;
  aspect-ratio: 16 / 9;
  display: block;
  margin: 0 auto;
}

/* 目次リンク先のh5要素にネガティブマージン */
h5 {
  scroll-margin-top: 400px;
}