:root {
    --primary-color: #1E3A8A;
    --secondary-color: #10B981;
    --accent-color: #F59E0B;
    --text-light: #ffffff;
    --text-dark: #333333;
    --bg-light: #f9fafb;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  }

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

  body {
    font-family: 'Montserrat', 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8f0 100%);
    min-height: 100%;
  }

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

  header {
    background: linear-gradient(135deg, var(--primary-color) 0%, #0f2c6b 100%);
    color: var(--text-light);
    padding: 2rem 0;
    position: relative;
    overflow: hidden;
  }

  header::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 10px;
    background: linear-gradient(90deg, var(--accent-color), var(--secondary-color));
  }

  .header-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    position: relative;
    z-index: 2;
  }

  .notice {
    background-color: rgba(255, 255, 255, 0.2);
    padding: 10px 20px;
    border-radius: 30px;
    font-size: 14px;
    margin-bottom: 20px;
    backdrop-filter: blur(5px);
  }

  h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  }

  .header-desc {
    max-width: 800px;
    margin: 0 auto 2rem;
    font-size: 1.1rem;
    opacity: 0.9;
  }

  .nav-container {
    width: 100%;
    background-color: rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 10px;
    padding: 10px;
  }

  nav {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
  }

  .nav-item {
    margin: 0 15px;
    position: relative;
  }

  .nav-item a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    padding: 10px 0;
    display: block;
    transition: all 0.3s ease;
  }

  .nav-item a:hover {
    color: var(--accent-color);
  }

  .nav-item a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-color);
    transition: width 0.3s ease;
  }

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

  main {
    padding: 3rem 0;
  }

  article {
    background-color: var(--text-light);
    border-radius: 15px;
    box-shadow: var(--shadow);
    padding: 2.5rem;
    margin-bottom: 3rem;
  }

  h2 {
    font-size: 1.8rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 10px;
  }

  h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--accent-color), var(--secondary-color));
  }

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

  p {
    margin-bottom: 1.5rem;
    font-size: 1.05rem;
    line-height: 1.7;
  }

  strong {
    color: var(--primary-color);
  }

  .img-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-around;
    margin: 2rem 0;
    gap: 20px;
  }

  .img-card {
    width: 300px;
    height: 300px;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
  }

  .img-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
  }

  .img-card img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
  }

  .img-card:hover img {
    transform: scale(1.05);
  }

  pre {
    background: linear-gradient(135deg, #2c3e50 0%, #1a2533 100%);
    border-radius: 10px;
    padding: 1.5rem;
    margin: 2rem 0;
    overflow-x: auto;
    box-shadow: var(--shadow);
  }

  code {
    font-family: 'Courier New', monospace;
    color: #f8f8f2;
    font-size: 0.95rem;
  }

  .code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.2);
    padding: 8px 15px;
    border-radius: 8px 8px 0 0;
    margin-bottom: 15px;
  }

  .code-title {
    color: var(--accent-color);
    font-weight: bold;
  }

  .language-css {
    color: #66d9ef;
  }

  .property {
    color: #a6e22e;
  }

  .value {
    color: #ae81ff;
  }

  .comment {
    color: #75715e;
  }

  footer {
    background: linear-gradient(135deg, var(--primary-color) 0%, #0f2c6b 100%);
    color: var(--text-light);
    padding: 2rem 0;
    text-align: center;
  }

  .footer-content {
    max-width: 800px;
    margin: 0 auto;
  }

  .footer-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    margin: 1rem 0;
  }

  .footer-link {
    color: var(--text-light);
    text-decoration: none;
    margin: 0 15px;
    transition: color 0.3s ease;
  }

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

  @media (max-width: 768px) {
    h1 {
      font-size: 2rem;
    }

    article {
      padding: 1.5rem;
    }

    .img-card {
      width: 100%;
      max-width: 400px;
    }
  }

  @media (max-width: 480px) {
    .nav-item {
      margin: 0 10px;
    }

    h2 {
      font-size: 1.5rem;
    }

    h3 {
      font-size: 1.3rem;
    }
  }