@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@700&family=Open+Sans:wght@400;600&display=swap');
  
  :root {
    --primary: #1E3A8A;
    --accent: #F59E0B;
    --bg: #f5f5f5;
    --text: #333333;
    --light: #ffffff;
    --gray: #e0e0e0;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  }
  
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    background: var(--bg);
    color: var(--text);
    font-family: 'Open Sans', sans-serif;
    line-height: 1.6;
    overflow-x: hidden;
  }
  
  .wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
  }
  
  .notification {
    background: linear-gradient(135deg, var(--primary), #3B82F6);
    color: white;
    padding: 15px;
    text-align: center;
    font-weight: 600;
    box-shadow: var(--shadow);
    margin-bottom: 30px;
    border-radius: 0 0 8px 8px;
  }
  
  header {
    background: var(--light);
    padding: 30px 0;
    margin-bottom: 40px;
    box-shadow: var(--shadow);
    border-radius: 8px;
    position: relative;
    overflow: hidden;
  }
  
  header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
  }
  
  h1, h2, h3, h4 {
    font-family: 'Roboto', sans-serif;
    color: var(--primary);
    margin-bottom: 20px;
  }
  
  h1 {
    font-size: 2.5rem;
    text-align: center;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    position: relative;
    padding-bottom: 15px;
  }
  
  h1::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: var(--accent);
    border-radius: 2px;
  }
  
  h2 {
    font-size: 1.8rem;
    margin-top: 40px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--gray);
  }
  
  h3 {
    font-size: 1.4rem;
    margin-top: 30px;
    color: var(--accent);
  }
  
  p {
    margin-bottom: 20px;
    font-size: 1.1rem;
  }
  
  .grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin: 40px 0;
  }
  
  .card {
    background: var(--light);
    border-radius: 10px;
    padding: 25px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    position: relative;
    overflow: hidden;
  }
  
  .card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
  }
  
  .card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 5px;
    height: 100%;
    background: linear-gradient(to bottom, var(--primary), var(--accent));
  }
  
  .img-container {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin: 30px 0;
    justify-content: center;
  }
  
  .img-box {
    width: 150px;
    height: 150px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease;
  }
  
  .img-box:hover {
    transform: scale(1.05);
  }
  
  .img-box img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    filter: grayscale(20%);
    transition: filter 0.3s ease;
  }
  
  .img-box:hover img {
    filter: grayscale(0%);
  }
  
  pre {
    background: #2d2d2d;
    color: #f8f8f2;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 25px 0;
    font-size: 0.95rem;
    line-height: 1.5;
    position: relative;
  }
  
  pre::before {
    content: 'CSS';
    position: absolute;
    top: 0;
    right: 0;
    background: var(--accent);
    color: white;
    padding: 3px 10px;
    font-size: 0.8rem;
    border-radius: 0 0 0 8px;
  }
  
  code {
    font-family: 'Courier New', monospace;
  }
  
  table {
    width: 100%;
    border-collapse: collapse;
    margin: 25px 0;
    box-shadow: var(--shadow);
    border-radius: 8px;
    overflow: hidden;
  }
  
  th, td {
    padding: 12px 15px;
    text-align: left;
  }
  
  th {
    background: var(--accent);
    color: white;
    font-weight: 600;
  }
  
  tr:nth-child(even) {
    background: rgba(0, 0, 0, 0.02);
  }
  
  tr:hover {
    background: rgba(30, 58, 138, 0.05);
  }
  
  .nav-tabs {
    display: flex;
    list-style: none;
    margin: 30px 0;
    border-bottom: 2px solid var(--gray);
  }
  
  .nav-tabs li {
    margin-right: 20px;
    position: relative;
  }
  
  .nav-tabs a {
    display: block;
    padding: 10px 0;
    color: var(--text);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
  }
  
  .nav-tabs a:hover {
    color: var(--accent);
  }
  
  .nav-tabs a.active {
    color: var(--primary);
  }
  
  .nav-tabs a.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--accent);
    border-radius: 2px 2px 0 0;
    animation: tabUnderline 0.3s ease-out;
  }
  
  @keyframes tabUnderline {
    from { width: 0 }
    to { width: 100% }
  }
  
  .btn {
    display: inline-block;
    background: var(--primary);
    color: white;
    padding: 12px 25px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    margin: 10px 0;
  }
  
  .btn:hover {
    background: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(245, 158, 11, 0.3);
  }
  
  .highlight {
    background: rgba(245, 158, 11, 0.1);
    padding: 2px 5px;
    border-radius: 3px;
    font-weight: 600;
  }
  
  .accordion {
    margin: 30px 0;
  }
  
  .accordion-item {
    margin-bottom: 10px;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
  }
  
  .accordion-header {
    background: var(--light);
    padding: 15px 20px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
  }
  
  .accordion-header:hover {
    background: rgba(30, 58, 138, 0.05);
  }
  
  .accordion-content {
    background: var(--light);
    padding: 0 20px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
  }
  
  .accordion-item.active .accordion-content {
    padding: 20px;
    max-height: 500px;
  }
  
  .floating {
    animation: float 6s ease-in-out infinite;
  }
  
  @keyframes float {
    0%, 100% { transform: translateY(0) }
    50% { transform: translateY(-10px) }
  }
  
  @media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    h3 { font-size: 1.2rem; }
    
    .grid-container {
      grid-template-columns: 1fr;
    }
    
    .img-box {
      width: 120px;
      height: 120px;
    }
  }