:root {
    --primary: #0f2027;
    --secondary: #203a43;
    --accent: #fca311;
    --text: #ffffff;
    --card-bg: rgba(255, 255, 255, 0.1);
    --transition: all 0.3s ease;
  }

  @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700&display=swap');

  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }

  body {
    font-family: 'Roboto', sans-serif;
    color: var(--text);
    background: linear-gradient(135deg, var(--primary), var(--secondary), #2c5364);
    animation: gradientAnimation 15s ease infinite;
    background-size: 400% 400%;
    line-height: 1.6;
    position: relative;
    overflow-x: hidden;
  }

  @keyframes gradientAnimation {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
  }

  .particles {
    position: absolute;
    width: 100%;
    height: 100%;
    background: url('https://images.gptkong.com/demo/sample1.png') repeat;
    opacity: 0.1;
    pointer-events: none;
    animation: particlesMove 20s linear infinite;
    z-index: -1;
  }

  @keyframes particlesMove {
    from { transform: translateY(0); }
    to { transform: translateY(-1000px); }
  }

  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 100px 20px;
  }

  .header {
    text-align: center;
    margin-bottom: 60px;
    position: relative;
  }

  .header h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    background: linear-gradient(90deg, var(--accent), #ffffff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    animation: textGlow 2s ease-in-out infinite alternate;
  }

  @keyframes textGlow {
    from { text-shadow: 0 0 10px rgba(252, 163, 17, 0.5); }
    to { text-shadow: 0 0 20px rgba(252, 163, 17, 0.8); }
  }

  .header p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto;
    color: rgba(255, 255, 255, 0.8);
  }

  .notice {
    background: rgba(0, 0, 0, 0.3);
    padding: 15px;
    border-left: 4px solid var(--accent);
    margin: 30px 0;
    font-size: 0.9rem;
    border-radius: 0 5px 5px 0;
  }

  article {
    background: rgba(0, 0, 0, 0.2);
    border-radius: 15px;
    padding: 40px;
    margin-bottom: 60px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    backdrop-filter: blur(10px);
  }

  article h2 {
    font-size: 2rem;
    margin-bottom: 30px;
    color: var(--accent);
    position: relative;
    padding-bottom: 15px;
  }

  article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100px;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), transparent);
  }

  article h3 {
    font-size: 1.5rem;
    margin: 30px 0 20px;
    color: #ffffff;
  }

  article p {
    margin-bottom: 20px;
    font-size: 1.1rem;
    line-height: 1.8;
  }

  pre {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 8px;
    padding: 20px;
    margin: 25px 0;
    overflow-x: auto;
    border-left: 4px solid var(--accent);
    font-family: 'Roboto Mono', monospace;
    position: relative;
  }

  pre::before {
    content: 'CSS';
    position: absolute;
    top: 0;
    right: 0;
    background: var(--accent);
    color: #000;
    padding: 2px 10px;
    font-size: 0.8rem;
    border-radius: 0 0 0 5px;
  }

  code {
    font-family: 'Roboto Mono', monospace;
    color: #f8f8f2;
  }

  .gallery {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
    margin: 40px 0;
  }

  .gallery img {
    width: 100%;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    transition: var(--transition);
    aspect-ratio: 1/1;
    object-fit: cover;
  }

  .gallery img:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.4);
  }

  .navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.7);
    padding: 15px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    backdrop-filter: blur(10px);
  }

  .navbar-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text);
    text-decoration: none;
  }

  .navbar-nav {
    display: flex;
    gap: 30px;
  }

  .nav-link {
    color: var(--text);
    text-decoration: none;
    font-size: 1rem;
    transition: var(--transition);
    position: relative;
  }

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

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

  .sidebar {
    position: fixed;
    left: 0;
    top: 60px;
    width: 250px;
    height: calc(100% - 60px);
    background: rgba(20, 33, 61, 0.9);
    transform: translateX(-100%);
    transition: var(--transition);
    z-index: 999;
    backdrop-filter: blur(10px);
  }

  .sidebar.active {
    transform: translateX(0);
  }

  .sidebar ul {
    list-style: none;
    padding: 30px;
  }

  .sidebar ul li {
    margin: 25px 0;
  }

  .sidebar ul li a {
    color: var(--text);
    text-decoration: none;
    font-size: 1rem;
    transition: var(--transition);
    display: block;
    padding: 8px 0;
  }

  .sidebar ul li a:hover {
    color: var(--accent);
    transform: translateX(10px);
  }

  .toggle-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text);
    font-size: 1.5rem;
    cursor: pointer;
  }

  .footer {
    background: rgba(20, 33, 61, 0.9);
    padding: 50px 30px;
    text-align: center;
    margin-top: 60px;
    backdrop-filter: blur(10px);
  }

  .footer p {
    margin-bottom: 20px;
    color: rgba(255, 255, 255, 0.7);
  }

  .footer-links {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-bottom: 30px;
  }

  .footer-link {
    color: var(--text);
    text-decoration: none;
    transition: var(--transition);
  }

  .footer-link:hover {
    color: var(--accent);
  }

  .social-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 30px;
  }

  .social-link {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
  }

  .social-link:hover {
    background: var(--accent);
    transform: translateY(-5px);
  }

  @media (max-width: 768px) {
    .navbar-nav {
      display: none;
    }
    .toggle-btn {
      display: block;
    }
    .header h1 {
      font-size: 2rem;
    }
    article {
      padding: 30px 20px;
    }
    .gallery {
      grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    }
  }