:root {
    --primary-70: #8B4513;
    --primary-60: #A0522D;
    --primary-50: #B87333;
    --secondary-25: #6B8E23;
    --secondary-15: #556B2F;
    --accent-5: #4682B4;
    --bg-light: #F5F5DC;
    --text-dark: #333;
    --text-light: #FFF;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
  }

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

  body {
    font-family: 'Times New Roman', Times, serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
    background-image: linear-gradient(135deg, var(--primary-60) 0%, var(--secondary-25) 25%, var(--accent-5) 50%, var(--bg-light) 75%, #D3D3D3 100%);
    background-size: 400% 400%;
    animation: gradientAnimation 15s ease infinite;
    padding-top: 80px;
  }

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

  .header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--primary-70);
    color: var(--text-light);
    padding: 1rem;
    box-shadow: var(--box-shadow);
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
  }

  .header h1 {
    font-size: 1.5rem;
    letter-spacing: 1px;
  }

  .notice {
    background-color: rgba(255, 255, 255, 0.9);
    color: var(--primary-70);
    padding: 0.5rem 1rem;
    border-radius: var(--border-radius);
    font-size: 0.9rem;
    box-shadow: var(--box-shadow);
  }

  .container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 2rem;
  }

  .sidebar {
    background-color: var(--primary-70);
    color: var(--text-light);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--box-shadow);
    height: fit-content;
    position: sticky;
    top: 100px;
  }

  .sidebar h3 {
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  }

  .sidebar ul {
    list-style: none;
  }

  .sidebar li {
    margin-bottom: 0.5rem;
  }

  .sidebar a {
    color: var(--text-light);
    text-decoration: none;
    display: block;
    padding: 0.5rem;
    border-radius: var(--border-radius);
    transition: var(--transition);
  }

  .sidebar a:hover {
    background-color: rgba(255, 255, 255, 0.1);
    transform: translateX(5px);
  }

  .content {
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: var(--border-radius);
    padding: 2rem;
    box-shadow: var(--box-shadow);
  }

  article h2 {
    color: var(--primary-70);
    margin-bottom: 1.5rem;
    font-size: 2rem;
    position: relative;
    padding-bottom: 0.5rem;
  }

  article h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-70), var(--secondary-25));
  }

  article h3 {
    color: var(--secondary-25);
    margin: 1.5rem 0 1rem;
    font-size: 1.5rem;
  }

  article p {
    margin-bottom: 1rem;
    font-size: 1.1rem;
  }

  pre {
    background-color: #f8f8f8;
    border-left: 4px solid var(--accent-5);
    border-radius: var(--border-radius);
    padding: 1rem;
    margin: 1rem 0;
    overflow-x: auto;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9rem;
    box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.1);
  }

  code {
    background-color: #f8f8f8;
    padding: 0.2rem 0.4rem;
    border-radius: 3px;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.9rem;
    color: var(--primary-70);
  }

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

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

  .image-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.15);
  }

  .image-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-bottom: 1px solid #eee;
  }

  .image-card .caption {
    padding: 1rem;
    background-color: white;
  }

  .image-card h4 {
    color: var(--primary-70);
    margin-bottom: 0.5rem;
  }

  .image-card p {
    color: var(--text-dark);
    font-size: 0.9rem;
  }

  table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
    box-shadow: var(--box-shadow);
    border-radius: var(--border-radius);
    overflow: hidden;
  }

  th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #ddd;
  }

  th {
    background-color: var(--primary-70);
    color: var(--text-light);
  }

  tr:nth-child(even) {
    background-color: #f9f9f9;
  }

  tr:hover {
    background-color: #f1f1f1;
  }

  ol, ul {
    margin: 1rem 0 1rem 2rem;
  }

  li {
    margin-bottom: 0.5rem;
  }

  .button {
    display: inline-block;
    background-color: var(--primary-70);
    color: var(--text-light);
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
    box-shadow: 0 4px 0 var(--primary-60);
    margin: 0.5rem 0;
  }

  .button:hover {
    background-color: var(--primary-60);
    transform: translateY(-2px);
    box-shadow: 0 6px 0 var(--primary-70);
  }

  .button:active {
    transform: translateY(0);
    box-shadow: 0 2px 0 var(--primary-70);
  }

  .accordion {
    margin: 1.5rem 0;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
  }

  .accordion-header {
    background-color: var(--primary-70);
    color: var(--text-light);
    padding: 1rem;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: var(--transition);
  }

  .accordion-header:hover {
    background-color: var(--primary-60);
  }

  .accordion-content {
    background-color: white;
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }

  .accordion-content-inner {
    padding: 1.5rem;
  }

  .accordion.active .accordion-content {
    max-height: 1000px;
  }

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

  @media (max-width: 768px) {
    body {
      padding-top: 70px;
    }
    
    .header h1 {
      font-size: 1.2rem;
    }
    
    .notice {
      font-size: 0.8rem;
    }
    
    .content {
      padding: 1.5rem;
    }
    
    article h2 {
      font-size: 1.8rem;
    }
    
    article h3 {
      font-size: 1.3rem;
    }
  }

  @media (max-width: 576px) {
    .image-grid {
      grid-template-columns: 1fr;
    }
    
    .header {
      flex-direction: column;
      text-align: center;
      gap: 0.5rem;
    }
    
    .header h1 {
      margin-bottom: 0.5rem;
    }
  }