:root {
  --primary-color: #0D47A1;
  --secondary-color: #ECEFF1;
  --white-color: #FFFFFF;
  --accent-orange: #FFC107;
  --accent-green: #8BC34A;
  --text-dark: #333333;
  --shadow-sm: 0 4px 6px rgba(0,0,0,0.1);
  --shadow-md: 0 10px 15px rgba(0,0,0,0.1);
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

.header {
  background: var(--primary-color);
  color: white;
  padding: 2rem 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg, var(--accent-orange), var(--accent-green));
}

.header h1 {
  font-size: 2.5rem;
  margin: 0;
  position: relative;
  z-index: 1;
  text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.header p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 1rem auto 0;
  opacity: 0.9;
}

.container {
  max-width: 1200px;
  margin: 3rem auto;
  padding: 0 2rem;
}

.notice {
  background: var(--secondary-color);
  padding: 1rem;
  border-radius: 8px;
  margin-bottom: 2rem;
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.article-container {
  background: white;
  border-radius: 12px;
  padding: 2rem;
  box-shadow: var(--shadow-md);
  margin-bottom: 3rem;
}

article {
  max-width: 900px;
  margin: 0 auto;
}

article h2 {
  color: var(--primary-color);
  font-size: 2rem;
  margin-top: 2rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--secondary-color);
}

article h3 {
  color: var(--primary-color);
  font-size: 1.5rem;
  margin-top: 1.5rem;
}

article p {
  font-size: 1.1rem;
  margin: 1rem 0;
}

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

.image-card {
  border-radius: 8px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.image-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
}

.image-card img {
  width: 100%;
  height: auto;
  display: block;
}

pre {
  background: #f8f9fa;
  padding: 1.5rem;
  border-radius: 8px;
  overflow-x: auto;
  margin: 1.5rem 0;
  border-left: 4px solid var(--primary-color);
}

code {
  font-family: 'Courier New', monospace;
  color: #333;
}

.nav-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 2rem 0;
}

.nav-link {
  padding: 0.8rem 1.5rem;
  background: var(--primary-color);
  color: white;
  border-radius: 50px;
  text-decoration: none;
  transition: var(--transition);
  font-weight: 500;
}

.nav-link:hover {
  background: var(--accent-orange);
  transform: translateY(-2px);
}

.footer {
  text-align: center;
  padding: 2rem;
  background: var(--primary-color);
  color: white;
  margin-top: 3rem;
}

@media (max-width: 768px) {
  .header h1 {
    font-size: 2rem;
  }
  
  .container {
    padding: 0 1rem;
  }
  
  .image-grid {
    grid-template-columns: 1fr;
  }
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.animate {
  animation: fadeIn 0.6s ease-out forwards;
}

.delay-1 { animation-delay: 0.2s; }
.delay-2 { animation-delay: 0.4s; }
.delay-3 { animation-delay: 0.6s; }