:root {
    --primary: #007BFF;
    --secondary: #FF9800;
    --accent: #E91E63;
    --light: #F5F5F5;
    --dark: #212121;
    --gradient: linear-gradient(135deg, #7B1FA2, #E91E63);
    --card-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    --transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.1);
  }

  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Montserrat', 'Open Sans', sans-serif;
  }

  body {
    background: var(--light);
    color: var(--dark);
    line-height: 1.7;
    overflow-x: hidden;
  }

  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
  }

  /* Header Styles */
  .header {
    background: var(--gradient);
    padding: 6rem 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    border-radius: 0 0 30px 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  }

  .header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center right/contain;
    opacity: 0.15;
  }

  .header h1 {
    font-size: 3.5rem;
    color: white;
    margin-bottom: 1.5rem;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    position: relative;
    z-index: 2;
  }

  .header p {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.9);
    max-width: 700px;
    margin: 0 auto;
    position: relative;
    z-index: 2;
  }

  .notice {
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    padding: 1rem;
    border-radius: 10px;
    display: inline-block;
    margin-top: 2rem;
    font-weight: bold;
    color: white;
    position: relative;
    z-index: 2;
    border: 1px solid rgba(255, 255, 255, 0.3);
  }

  /* Navigation */
  .nav {
    position: sticky;
    top: 0;
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    padding: 1rem 0;
    backdrop-filter: blur(5px);
  }

  .nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
  }

  .nav-logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary);
    text-decoration: none;
  }

  .nav-links {
    display: flex;
    gap: 2rem;
  }

  .nav-link {
    color: var(--dark);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
  }

  .nav-link:hover {
    color: var(--primary);
  }

  .nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
  }

  .nav-link:hover::after {
    width: 100%;
  }

  /* Article Styles */
  .article-container {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 3rem;
    padding: 3rem 0;
  }

  .sidebar {
    position: sticky;
    top: 100px;
    align-self: start;
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--card-shadow);
  }

  .sidebar-title {
    font-size: 1.2rem;
    margin-bottom: 1.5rem;
    color: var(--primary);
    position: relative;
    padding-bottom: 0.5rem;
  }

  .sidebar-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 3px;
    background: var(--gradient);
    border-radius: 3px;
  }

  .sidebar-nav {
    list-style: none;
  }

  .sidebar-item {
    margin-bottom: 0.8rem;
  }

  .sidebar-link {
    color: var(--dark);
    text-decoration: none;
    transition: var(--transition);
    display: block;
    padding: 0.5rem 0;
    border-left: 3px solid transparent;
    padding-left: 1rem;
  }

  .sidebar-link:hover {
    color: var(--primary);
    border-left: 3px solid var(--primary);
    padding-left: 1.5rem;
  }

  .article {
    background: white;
    padding: 3rem;
    border-radius: 15px;
    box-shadow: var(--card-shadow);
  }

  .article h2 {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 0.5rem;
  }

  .article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 80px;
    height: 4px;
    background: var(--gradient);
    border-radius: 2px;
  }

  .article h3 {
    font-size: 1.5rem;
    color: var(--secondary);
    margin: 2rem 0 1rem;
  }

  .article p {
    font-size: 1.1rem;
    margin-bottom: 1.5rem;
    line-height: 1.8;
  }

  /* Code Blocks */
  pre {
    background: #282c34;
    border-radius: 10px;
    padding: 1.5rem;
    margin: 2rem 0;
    overflow: auto;
    position: relative;
  }

  pre::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 40px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 10px 10px 0 0;
  }

  code {
    font-family: 'Fira Code', monospace;
    color: #abb2bf;
    font-size: 0.9rem;
    line-height: 1.6;
  }

  /* Image Gallery */
  .image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin: 2rem 0;
  }

  .gallery-item {
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
    position: relative;
  }

  .gallery-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
  }

  .gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
  }

  /* Cards */
  .card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin: 3rem 0;
  }

  .card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
  }

  .card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
  }

  .card-img {
    height: 200px;
    overflow: hidden;
  }

  .card-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
  }

  .card:hover .card-img img {
    transform: scale(1.1);
  }

  .card-content {
    padding: 1.5rem;
  }

  .card-title {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
    color: var(--primary);
  }

  .card-desc {
    color: #666;
    font-size: 0.95rem;
  }

  /* Animations */
  @keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
  }

  .floating {
    animation: float 6s ease-in-out infinite;
  }

  /* Responsive */
  @media (max-width: 992px) {
    .article-container {
      grid-template-columns: 1fr;
    }
    
    .sidebar {
      position: static;
      margin-bottom: 2rem;
    }
  }

  @media (max-width: 768px) {
    .header h1 {
      font-size: 2.5rem;
    }
    
    .nav-links {
      display: none;
    }
    
    .article {
      padding: 2rem;
    }
  }