:root {
  --primary: #001f3f;
  --secondary: #0074D9;
  --accent: #FFD700;
  --highlight: #FF851B;
  --bg-light: #f8f9fa;
  --text-dark: #333333;
  --text-light: #ffffff;
  --card-shadow: 0 10px 30px rgba(0, 31, 63, 0.1);
}

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

body {
  font-family: 'Roboto', sans-serif;
  color: var(--text-dark);
  background: linear-gradient(135deg, #f5f7fa 0%, #e4e8eb 100%);
  line-height: 1.6;
  overflow-x: hidden;
}

header {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: var(--accent);
  padding: 2rem 0;
  text-align: center;
  position: relative;
  overflow: hidden;
  margin-bottom: 3rem;
}

header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('https://images.gptkong.com/demo/sample3.png') center/cover no-repeat;
  opacity: 0.1;
  z-index: 0;
}

h1, h2, h3, h4 {
  font-family: 'Montserrat', sans-serif;
  color: var(--primary);
  margin-bottom: 1.5rem;
  position: relative;
}

h2::after {
  content: '';
  display: block;
  width: 80px;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--highlight));
  margin: 1rem auto;
  border-radius: 2px;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 3rem;
  margin-bottom: 4rem;
}

.hero-text {
  flex: 1;
  padding: 2rem;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  position: relative;
  z-index: 1;
}

.hero-image {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-image img {
  width: 100%;
  max-width: 400px;
  border-radius: 12px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
  transform: rotate(-5deg);
  transition: transform 0.5s ease;
}

.hero-image img:hover {
  transform: rotate(0deg) scale(1.05);
}

article {
  background: white;
  border-radius: 12px;
  padding: 3rem;
  box-shadow: var(--card-shadow);
  margin-bottom: 3rem;
}

pre {
  background: #2d2d2d;
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  overflow: auto;
  position: relative;
}

code {
  font-family: 'Fira Code', monospace;
  color: #f8f8f2;
  font-size: 0.9em;
}

.code-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #1e1e1e;
  color: #d4d4d4;
  padding: 0.5rem 1rem;
  border-radius: 8px 8px 0 0;
  font-family: 'Fira Code', monospace;
  font-size: 0.8em;
}

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

.card {
  background: white;
  border-radius: 12px;
  padding: 2rem;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.card::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(to bottom, var(--accent), var(--highlight));
}

.image-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.gallery-item {
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
  position: relative;
}

.gallery-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  transition: transform 0.5s ease;
}

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

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

.gallery-item::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(to top, rgba(0, 0, 0, 0.5), transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.gallery-item:hover::after {
  opacity: 1;
}

.note {
  background: linear-gradient(135deg, rgba(0, 31, 63, 0.05), rgba(0, 116, 217, 0.05));
  border-left: 4px solid var(--secondary);
  padding: 1.5rem;
  margin: 1.5rem 0;
  border-radius: 0 8px 8px 0;
}

.ref {
  font-size: 0.8em;
  text-align: center;
  color: #666;
  margin-top: 3rem;
  padding: 1rem;
  border-top: 1px solid #eee;
}

@media (max-width: 768px) {
  .hero {
    flex-direction: column;
  }
  
  .hero-image img {
    max-width: 100%;
  }
  
  article {
    padding: 2rem 1.5rem;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
  }
}

@keyframes float {
  0% { transform: translateY(0px); }
  50% { transform: translateY(-15px); }
  100% { transform: translateY(0px); }
}

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

.highlight {
  background: linear-gradient(90deg, rgba(255, 215, 0, 0.2), rgba(255, 215, 0, 0));
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
}