.course-catalog-page {
    background:
      radial-gradient(circle at top left, rgba(13, 110, 253, 0.08), transparent 24%),
      radial-gradient(circle at top right, rgba(102, 16, 242, 0.08), transparent 20%),
      linear-gradient(180deg, #f8fbff 0%, #eef4fb 100%);
    min-height: 100vh;
  }

  .catalog-hero {
    background: linear-gradient(135deg, #0d3b8e 0%, #3b1f8f 100%);
    color: #fff;
    border-radius: 2rem;
    padding: 2.5rem;
    box-shadow: 0 20px 55px rgba(15, 23, 42, 0.16);
    position: relative;
    overflow: hidden;
  }

  .catalog-hero::before {
    content: "";
    position: absolute;
    width: 280px;
    height: 280px;
    top: -80px;
    right: -70px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.08);
  }

  .catalog-hero::after {
    content: "";
    position: absolute;
    width: 180px;
    height: 180px;
    bottom: -50px;
    left: -40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.06);
  }

  .catalog-hero > .row {
    position: relative;
    z-index: 1;
  }

  .catalog-badge {
    display: inline-flex;
    align-items: center;
    background: rgba(255,255,255,0.12);
    border: 1px solid rgba(255,255,255,0.18);
    border-radius: 999px;
    padding: 0.55rem 1rem;
    font-weight: 700;
    font-size: 0.92rem;
  }

  .catalog-title {
    font-size: clamp(1.75rem, 3vw, 2.45rem);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 0;
  }

  .catalog-subtitle {
    font-size: 1.05rem;
    line-height: 1.85;
    color: rgba(255,255,255,0.88);
    max-width: 850px;
  }

  .catalog-highlight-card {
    background: rgba(255,255,255,0.12);
    border: 1px solid rgba(255,255,255,0.14);
    border-radius: 1.5rem;
    padding: 1.5rem;
    backdrop-filter: blur(10px);
    box-shadow: 0 12px 30px rgba(0,0,0,0.12);
  }

  .highlight-icon {
    width: 64px;
    height: 64px;
    border-radius: 1rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: rgba(255,255,255,0.16);
    font-size: 1.6rem;
    margin-bottom: 1rem;
  }

  .catalog-filter-card {
    background: rgba(255,255,255,0.92);
    border: 1px solid rgba(13,110,253,0.16);
    border-radius: 1.5rem;
    padding: 1.5rem;
    box-shadow: 0 16px 36px rgba(15, 23, 42, 0.09);
  }

  .filter-label {
    font-weight: 700;
    color: #0f172a;
    margin-bottom: 0.55rem;
  }

  .search-input-wrap {
    position: relative;
  }

  .search-icon {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: #64748b;
    z-index: 2;
  }

  .filter-input {
    min-height: 54px;
    padding-left: 2.8rem;
    border-radius: 999px;
    border: 1px solid #aebfd3;
    color: #0f172a;
  }

  .filter-select {
    min-height: 54px;
    border-radius: 999px;
    border: 1px solid #aebfd3;
    color: #0f172a;
  }

  .filter-input:focus,
  .filter-select:focus {
    border-color: #0d6efd;
    box-shadow: 0 0 0 0.25rem rgba(13,110,253,0.12);
  }

  .filter-btn,
  .reset-btn {
    border-radius: 999px;
    min-height: 48px;
    font-weight: 700;
  }

  .filter-btn {
    box-shadow: 0 8px 18px rgba(13, 110, 253, 0.2);
  }

  .filter-btn:hover,
  .reset-btn:hover {
    transform: translateY(-1px);
  }

  .catalog-results-header {
    align-items: end;
    border-bottom: 1px solid #d8e2ee;
    display: flex;
    justify-content: space-between;
    padding-bottom: 1rem;
  }

  .catalog-results-header h3 {
    font-weight: 800;
    color: #0f172a;
  }

  .summary-card {
    background: rgba(255,255,255,0.88);
    border: 1px solid rgba(13,110,253,0.08);
    border-radius: 1.3rem;
    padding: 1.2rem 1.1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: 0 10px 28px rgba(15, 23, 42, 0.06);
    height: 100%;
  }

  .summary-icon {
    width: 56px;
    height: 56px;
    border-radius: 1rem;
    background: linear-gradient(135deg, #0d6efd, #6610f2);
    color: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.35rem;
    flex-shrink: 0;
  }

  .summary-card h6 {
    font-weight: 800;
    margin-bottom: 0.35rem;
    color: #0f172a;
  }

  .summary-card p {
    color: #64748b;
    margin: 0;
  }

  .course-card {
    --course-accent: #0b63ce;
    --course-accent-dark: #084298;
    --course-soft: #eaf3ff;
    --course-border: #bdd8ff;
    background: rgba(255,255,255,0.92);
    border: 1px solid var(--course-border);
    border-top: 4px solid var(--course-accent);
    border-radius: 1.5rem;
    box-shadow: 0 14px 35px rgba(15, 23, 42, 0.07);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition:
      border-color 0.28s ease,
      box-shadow 0.28s ease,
      transform 0.28s ease;
  }

  .course-card.course-theme-blue {
    --course-accent: #0b63ce;
    --course-accent-dark: #084298;
    --course-soft: #eaf3ff;
    --course-border: #bdd8ff;
  }

  .course-card.course-theme-teal {
    --course-accent: #087f72;
    --course-accent-dark: #075f56;
    --course-soft: #e7f8f4;
    --course-border: #a9ded4;
  }

  .course-card.course-theme-plum {
    --course-accent: #8a2a8a;
    --course-accent-dark: #672067;
    --course-soft: #faecfa;
    --course-border: #e4b9e4;
  }

  .course-card.course-theme-amber {
    --course-accent: #b45309;
    --course-accent-dark: #873e07;
    --course-soft: #fff4e5;
    --course-border: #f1c98f;
  }

  .course-card.course-theme-green {
    --course-accent: #2f7d32;
    --course-accent-dark: #235e26;
    --course-soft: #edf8ed;
    --course-border: #b8ddb9;
  }

  .course-card.course-theme-rose {
    --course-accent: #b43c52;
    --course-accent-dark: #872d3e;
    --course-soft: #fff0f3;
    --course-border: #efbcc5;
  }

  .course-card:hover {
    transform: translateY(-7px);
    box-shadow: 0 24px 48px rgba(15, 23, 42, 0.14);
    border-color: var(--course-accent);
  }

  .course-card-top {
    background: linear-gradient(135deg, var(--course-soft), rgba(255, 255, 255, 0.82));
    border-bottom: 1px solid var(--course-border);
    padding: 1.2rem 1.2rem 0.9rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
  }

  .course-icon {
    width: 58px;
    height: 58px;
    border-radius: 1rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--course-accent);
    color: #fff;
    font-size: 1.35rem;
    box-shadow: 0 12px 24px rgba(15, 23, 42, 0.16);
    transition: transform 0.28s ease;
  }

  .course-card:hover .course-icon {
    transform: rotate(-4deg) scale(1.06);
  }

  .course-credit-badge {
    display: inline-flex;
    align-items: center;
    background: #fff;
    color: var(--course-accent-dark);
    border: 1px solid var(--course-border);
    border-radius: 999px;
    padding: 0.45rem 0.85rem;
    font-size: 0.86rem;
    font-weight: 700;
    text-align: center;
  }

  .course-card-body {
    background: linear-gradient(180deg, var(--course-soft) 0, #fff 3.5rem);
    padding: 1.2rem 1.2rem 0.8rem;
    flex-grow: 1;
  }

  .course-meta {
    color: #64748b;
    font-size: 0.92rem;
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    align-items: center;
  }

  .course-code {
    font-weight: 800;
    color: var(--course-accent);
  }

  .course-divider {
    color: #94a3b8;
  }

  .course-department {
    color: #475569;
    font-size: 0.92rem;
    font-weight: 600;
  }

  .course-department i {
    color: var(--course-accent);
  }

  .course-title {
    color: var(--course-accent-dark);
    font-size: 1.06rem;
    font-weight: 800;
    line-height: 1.45;
    margin-bottom: 0.75rem;
    padding-bottom: 0.65rem;
    position: relative;
  }

  .course-title::after {
    background: var(--course-accent);
    border-radius: 999px;
    bottom: 0;
    content: "";
    height: 3px;
    left: 0;
    position: absolute;
    transition: width 0.28s ease;
    width: 2.75rem;
  }

  .course-card:hover .course-title::after {
    width: 5rem;
  }

  .course-title a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s ease;
  }

  .course-title a:hover {
    color: var(--course-accent);
  }

  .course-title a:focus-visible {
    border-radius: 0.25rem;
    box-shadow: 0 0 0 0.2rem var(--course-soft);
    outline: 2px solid var(--course-accent);
    outline-offset: 3px;
  }

  .course-description {
    color: #64748b;
    line-height: 1.65;
    margin-bottom: 0;
  }

  .course-description.is-collapsible {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .course-description.is-collapsible.is-expanded {
    overflow: visible;
    white-space: normal;
  }

  .course-description-toggle {
    align-items: center;
    background: var(--course-soft);
    border: 1px solid var(--course-border);
    border-radius: 0.45rem;
    color: var(--course-accent-dark);
    display: inline-flex;
    font-size: 0.82rem;
    font-weight: 800;
    gap: 0.35rem;
    margin-top: 0.6rem;
    padding: 0.35rem 0.65rem;
    transition:
      background-color 0.2s ease,
      border-color 0.2s ease,
      color 0.2s ease,
      box-shadow 0.2s ease;
  }

  .course-description-toggle:hover {
    background: #fff;
    border-color: var(--course-accent);
    color: var(--course-accent);
  }

  .course-description-toggle:focus-visible {
    box-shadow: 0 0 0 0.2rem rgba(13, 110, 253, 0.2);
    outline: 0;
  }

  .course-description-toggle i {
    font-size: 0.75rem;
    transition: transform 0.2s ease;
  }

  .course-description-toggle[aria-expanded="true"] i {
    transform: rotate(180deg);
  }

  .course-card-footer {
    background: var(--course-soft);
    padding: 1rem 1.2rem 1.2rem;
    border-top: 1px solid var(--course-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
  }

  .course-prereq-info {
    color: #475569;
    font-weight: 700;
    font-size: 0.95rem;
  }

  .course-prereq-info i {
    color: var(--course-accent);
  }

  .course-link {
    display: inline-flex;
    align-items: center;
    gap: 0.2rem;
    font-weight: 700;
    color: var(--course-accent-dark);
    text-decoration: none;
    transition:
      color 0.2s ease,
      transform 0.2s ease;
  }

  .course-link:hover {
    color: var(--course-accent);
    transform: translateX(3px);
  }

  .empty-courses-state {
    background: rgba(255,255,255,0.92);
    border: 1px dashed rgba(13,110,253,0.18);
    border-radius: 1.5rem;
    padding: 3rem 1.5rem;
    box-shadow: 0 10px 24px rgba(15, 23, 42, 0.05);
  }

  .empty-icon {
    width: 82px;
    height: 82px;
    margin: 0 auto;
    border-radius: 50%;
    background: linear-gradient(135deg, rgba(13,110,253,0.12), rgba(102,16,242,0.10));
    color: #0d6efd;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
  }

  .catalog-pagination {
    align-items: center;
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
    margin-top: 2.25rem;
  }

  .catalog-page-status {
    color: #64748b;
    font-size: 0.9rem;
    font-weight: 700;
    margin: 0;
  }

  .catalog-pagination .pagination {
    flex-wrap: wrap;
    gap: 0.45rem;
  }

  .catalog-pagination .page-link {
    align-items: center;
    background: #fff;
    border: 1px solid #cbd8e8;
    border-radius: 0.6rem;
    color: #23436a;
    display: inline-flex;
    font-weight: 800;
    justify-content: center;
    min-height: 2.6rem;
    min-width: 2.6rem;
    padding: 0.5rem 0.8rem;
    transition:
      background-color 0.2s ease,
      border-color 0.2s ease,
      box-shadow 0.2s ease,
      color 0.2s ease,
      transform 0.2s ease;
  }

  .catalog-pagination .page-link:hover {
    background: #eef5ff;
    border-color: #7eadeb;
    color: #0b63ce;
    transform: translateY(-2px);
  }

  .catalog-pagination .page-link:focus-visible {
    box-shadow: 0 0 0 0.2rem rgba(11, 99, 206, 0.2);
    outline: 0;
  }

  .catalog-pagination .page-item.active .page-link {
    background: #0b63ce;
    border-color: #0b63ce;
    box-shadow: 0 8px 18px rgba(11, 99, 206, 0.24);
    color: #fff;
  }

  .catalog-pagination .page-item.disabled .page-link {
    background: #f1f5f9;
    border-color: #dce4ed;
    color: #94a3b8;
    transform: none;
  }

  .catalog-pagination .page-direction {
    gap: 0.45rem;
    min-width: 6.75rem;
  }

  @media (max-width: 991.98px) {
    .catalog-hero {
      padding: 1.75rem;
    }
  }

  @media (max-width: 575.98px) {
    .catalog-title {
      font-size: 1.7rem;
    }

    .course-card-footer {
      flex-direction: column;
      align-items: flex-start;
    }

    .catalog-pagination .page-direction {
      min-width: 2.6rem;
    }

    .catalog-pagination .page-direction span {
      display: none;
    }
  }

  @media (prefers-reduced-motion: reduce) {
    .filter-btn,
    .reset-btn,
    .course-card,
    .course-icon,
    .course-title::after,
    .course-link,
    .catalog-pagination .page-link {
      transition: none;
    }
  }