/* ================================
   CSS Variables & Base Styles
   ================================ */
   :root {
    --bg-primary: #faf9f6;
    --bg-secondary: #f5f4f0;
    --text-primary: #1a1a1a;
    --text-secondary: #555555;
    --text-muted: #888888;
    --accent-color: #2d5a7b;
    --accent-hover: #c96a3a;
    --border-color: rgba(0, 0, 0, 0.08);
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s ease;
    --max-width: 900px;
    --font-heading: 'Lexend', sans-serif;
    --font-body: 'Lexend', sans-serif;
  }
  
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  html {
    scroll-behavior: smooth;
  }
  
  body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }
  
  /* ================================
     Navigation
     ================================ */
  .navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(250, 249, 246, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    padding: 0 24px;
  }
  
  .nav-container {
    width: 100%;
    padding: 0 24px;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    height: 80px;
  }
  
  .nav-logo {
    display: flex;
    align-items: center;
    text-decoration: none;
  }
  
  
  
  .nav-links {
    display: flex;
    gap: 40px;
  }
  
  .nav-link {
    font-family: 'Lexend', sans-serif;
    font-size: 1.07rem;
    font-weight: 500;
    color: #888888;
    text-decoration: none;
    padding: 8px 0;
    position: relative;
    transition: var(--transition);
    letter-spacing: 0.08em;
  }
  
  .nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: -10px;
    width: 0;
    height: 2px;
    background: var(--accent-hover);
    transition: width 0.3s ease;
  }
  
  .nav-link:hover,
  .nav-link.active {
    color: #555555;
  }
  
  .nav-link:hover::after,
  .nav-link.active::after {
    width: calc(100% + 20px);
  }
  
  /* ================================
     Main Content
     ================================ */
  .main-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 110px 24px 60px;
    min-height: calc(100vh - 100px);
  }
  
  .tab-content {
    display: none;
    animation: fadeIn 0.4s ease;
  }
  
  .tab-content.active {
    display: block;
  }
  
  @keyframes fadeIn {
    from {
      opacity: 0;
      transform: translateY(10px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }
  
  /* ================================
     Typography
     ================================ */
  h1 {
    font-family: var(--font-heading);
    font-size: 1.75rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 40px;
    letter-spacing: -0.02em;
  }
  
  h2 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 20px;
    letter-spacing: -0.01em;
  }
  
  h3 {
    font-family: var(--font-body);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
  }
  
  a {
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition);
  }
  
  a:hover {
    color: var(--accent-hover);
  }
  
  strong {
    font-weight: 600;
  }
  
  /* ================================
     About Section
     ================================ */
  .about-header {
    display: flex;
    gap: 50px;
    margin-bottom: 30px;
    align-items: flex-start;
  }
  
  .about-text {
    flex: 1;
  }
  
  .name-heading {
    font-family: 'Georgia', serif;
    font-size: 2.2rem;
    font-weight: 600;
    color: #000000;
    margin-bottom: 20px;
    letter-spacing: -0.02em;
  }
  
  .about-text h1 {
    margin-bottom: 16px;
  }
  
  .bio {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    line-height: 1.6;
    text-align: justify;
  }
  
  .social-links {
    display: flex;
    flex-wrap: nowrap;
    gap: 6px;
    margin-top: 18px;
    padding-top: 14px;
    border-top: 1px solid var(--border-color);
  }
  
  .social-links a {
    font-size: 1rem;
    font-weight: 500;
    color: var(--accent-color);
    transition: var(--transition);
  }
  
  .social-links a:hover {
    color: var(--accent-hover);
  }
  
  .social-links a:not(:last-child)::after {
    content: '/';
    margin-left: 6px;
    color: var(--text-muted);
  }
  
  .about-image {
    flex-shrink: 0;
    width: 300px;
    padding-top: 80px;
  }
  
  .profile-container {
    width: 100%;
    aspect-ratio: 0.8;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
    position: relative;
  }
  
  .profile-photo {
    width: 100%;
    height: 100%;
    object-fit: cover;
    position: absolute;
    top: 0;
    left: 0;
    transition: opacity 0.5s ease;
  }
  
  .profile-photo-static {
    opacity: 1;
    z-index: 1;
  }
  
  .profile-photo-animated {
    opacity: 0;
    z-index: 2;
  }
  
  .profile-container:hover .profile-photo-static {
    opacity: 0;
  }
  
  .profile-container:hover .profile-photo-animated {
    opacity: 1;
  }
  
  /* ================================
     Sections
     ================================ */
  .section {
    margin-bottom: 50px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
  }
  
  .section:first-of-type {
    border-top: none;
    padding-top: 0;
  }
  
  /* News List */
  .news-list {
    list-style: none;
  }
  
  .news-list li {
    padding: 4px 0;
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.5;
  }
  
  .news-list .date {
    color: var(--text-muted);
    font-size: 0.85rem;
    margin-right: 12px;
    font-weight: 500;
  }
  
  /* Expandable News */
  .news-expanded {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, opacity 0.3s ease;
    opacity: 0;
  }
  
  .news-expanded.show {
    max-height: 500px;
    opacity: 1;
  }
  
  .news-expanded li:first-child {
    border-top: none;
  }
  
  .read-more-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-top: 16px;
    padding: 10px 20px;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-family: var(--font-body);
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
  }
  
  .read-more-btn:hover {
    background: var(--bg-secondary);
    color: var(--accent-color);
    border-color: var(--accent-color);
  }
  
  .read-more-btn .arrow {
    font-size: 0.85rem;
    transition: transform 0.3s ease;
  }
  
  /* Honors List */
  .honors-list {
    list-style: none;
  }
  
  .honors-list li {
    padding: 10px 0;
    padding-left: 20px;
    position: relative;
    color: var(--text-secondary);
    font-size: 0.95rem;
  }
  
  .honors-list li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--accent-color);
  }
  
  /* Teaching */
  .teaching-item {
    background: var(--bg-secondary);
    padding: 20px 24px;
    border-radius: 10px;
  }
  
  .teaching-item h3 {
    margin-bottom: 4px;
  }
  
  .teaching-item p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 4px;
  }
  
  .teaching-date {
    color: var(--text-muted) !important;
    font-size: 0.85rem !important;
  }
  
  /* Reviewing */
  .reviewing-list {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.8;
  }
  
  /* ================================
     Research Section
     ================================ */
  .year-section {
    margin-bottom: 50px;
  }
  
  .year-title {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: 24px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border-color);
  }
  
  .paper-item {
    display: flex;
    gap: 28px;
    padding: 24px 0;
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
  }
  
  .paper-item:last-child {
    border-bottom: none;
  }
  
  .paper-item:hover {
    background: linear-gradient(90deg, transparent, var(--bg-secondary), transparent);
  }
  
  .paper-image {
    flex-shrink: 0;
    width: 180px;
    height: 180px;
    border-radius: 4px;
    overflow: hidden;
    background: var(--bg-secondary);
    position: relative;
  }
  
  .paper-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: opacity 0.3s ease;
  }
  
  .paper-image .img-before {
    position: relative;
    z-index: 1;
  }
  
  .paper-image .img-after {
    position: absolute;
    top: 0;
    left: 0;
    opacity: 0;
    z-index: 2;
  }
  
  .paper-item:hover .paper-image .img-after {
    opacity: 1;
  }
  
  .paper-item:hover .paper-image .img-before {
    opacity: 0;
  }
  
  .paper-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
  }
  
  .paper-title {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
    line-height: 1.4;
  }
  
  .paper-authors {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 6px;
  }
  
  .paper-venue {
    font-size: 0.95rem;
    color: #555555;
    font-weight: 600;
    margin-bottom: 12px;
  }
  
  .paper-links {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
  }
  
  .paper-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--accent-color);
    padding: 4px 12px;
    background: rgba(45, 90, 123, 0.08);
    border-radius: 4px;
    transition: var(--transition);
  }
  
  .paper-links a:hover {
    background: var(--accent-hover);
    color: white;
  }
  
  /* ================================
     Art/Photography Section
     ================================ */
  .art-intro {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 50px;
    max-width: 600px;
  }
  
  .gallery-section {
    margin-bottom: 50px;
  }
  
  /* Photography section background */
  .photography-section h2 {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    font-weight: 500;
    color: white;
    margin-bottom: 24px;
    letter-spacing: -0.01em;
    background: linear-gradient(rgba(0,0,0,0.3), rgba(0,0,0,0.3)), url('images/image21.JPG');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    padding: 20px 30px;
    border-radius: 0;
    display: block;
    width: 100%;
    margin-top: 30px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    backdrop-filter: blur(1px);
    text-shadow: 0 2px 4px rgba(0,0,0,0.5);
  }
  
  /* Sketches section background */
  .sketches-section h2 {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    font-weight: 500;
    color: white;
    margin-bottom: 24px;
    letter-spacing: -0.01em;
    background: linear-gradient(rgba(0,0,0,0.3), rgba(0,0,0,0.3)), url('images/sketch_cover.png');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    padding: 20px 30px;
    border-radius: 0;
    display: block;
    width: 100%;
    margin-top: 30px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    backdrop-filter: blur(1px);
    text-shadow: 0 2px 4px rgba(0,0,0,0.5);
  }
  
  .gallery-grid {
    column-count: 3;
    column-gap: 6px;
  }
  
  .gallery-item {
    break-inside: avoid;
    margin-bottom: 6px;
    border-radius: 4px;
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
  }
  
  .gallery-item:hover {
    opacity: 0.9;
    box-shadow: var(--shadow-md);
  }
  
  .gallery-item img {
    width: 100%;
    height: auto;
    display: block;
  }
  
  .gallery-item.placeholder {
    aspect-ratio: 1;
    background: linear-gradient(135deg, var(--bg-secondary) 0%, #e8e6e0 100%);
    display: flex;
    align-items: center;
    justify-content: center;
  }
  
  /* Sketches section - use grid for spanning */
  .gallery-section:last-child .gallery-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    column-count: unset;
    gap: 6px;
  }
  
  .gallery-section:last-child .gallery-item {
    margin-bottom: 0;
  }
  
  .gallery-section:last-child .gallery-item.large {
    grid-column: span 2;
  }
  
  .placeholder-content {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
  }
  
  /* ================================
     Lightbox
     ================================ */
  .lightbox {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    z-index: 2000;
    justify-content: center;
    align-items: center;
    cursor: pointer;
  }
  
  .lightbox.active {
    display: flex;
  }
  
  .lightbox-img {
    max-width: 90%;
    max-height: 90%;
    object-fit: contain;
    border-radius: 8px;
    box-shadow: 0 10px 50px rgba(0, 0, 0, 0.5);
  }
  
  .lightbox-close {
    position: absolute;
    top: 20px;
    right: 30px;
    font-size: 40px;
    color: white;
    cursor: pointer;
    transition: var(--transition);
  }
  
  .lightbox-close:hover {
    color: var(--accent-hover);
  }
  
  /* ================================
     Footer
     ================================ */
  .footer {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 30px 24px 50px;
    text-align: center;
    border-top: 1px solid var(--border-color);
  }
  
  .footer p {
    font-size: 0.85rem;
    color: var(--text-muted);
  }
  
  /* ================================
     Responsive Design
     ================================ */
  @media (max-width: 768px) {
    .nav-container {
      flex-direction: column;
      height: auto;
      padding: 16px 0;
      gap: 12px;
    }
  
  
    .nav-links {
      gap: 24px;
    }
  
    .main-content {
      padding-top: 140px;
    }
  
    .about-header {
      flex-direction: column-reverse;
      gap: 30px;
    }
  
    .about-image {
      width: 220px;
      align-self: center;
      padding-top: 60px;
    }
  
    h1 {
      font-size: 2rem;
    }
  
    .name-heading {
      font-size: 1.8rem;
    }
  
    .main-logo {
      font-size: 2rem;
    }
  
    .paper-item {
      flex-direction: column;
      gap: 16px;
    }
  
    .paper-image {
      width: 100%;
      height: 180px;
    }
  
    .gallery-grid {
      grid-template-columns: repeat(3, 1fr);
    }
    
    .gallery-item.wide {
      grid-column: span 2;
    }
    
    .gallery-section:last-child .gallery-item.large {
      grid-column: span 2;
    }
  
    .social-links {
      gap: 16px;
    }
  }
  
  @media (max-width: 480px) {
  
    .nav-links {
      gap: 16px;
    }
  
    .nav-link {
      font-size: 0.85rem;
    }
  
    h1 {
      font-size: 1.75rem;
    }
  
    .name-heading {
      font-size: 1.5rem;
    }
  
    .gallery-grid {
      grid-template-columns: 1fr;
    }
    
    .gallery-item.landscape {
      grid-column: span 1;
    }
    
    .gallery-section:last-child .gallery-grid {
      grid-template-columns: repeat(2, 1fr);
    }
    
    .gallery-section:last-child .gallery-item.large {
      grid-column: span 1;
    }
  }