:root {
  --primary-color: #032B44;
  --background-color: #F5F7FA;
  --accent-color: #FF9800;
  --success-color: #3EB489;
  --text-color: #333333;
  --light-gray: #E1E5EE;
  --dark-gray: #6B7280;
  --gradient-blue: linear-gradient(135deg, #032B44 0%, #0A4B78 100%);
  --gradient-accent: linear-gradient(45deg, var(--accent-color), #FFA726);
}

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

body {
  font-family: 'Helvetica', sans-serif;
  background-color: var(--background-color);
  color: var(--text-color);
  line-height: 1.6;
  overflow-x: hidden;
}

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

/* Header Styles */
.header {
  background: var(--gradient-blue);
  color: white;
  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/sample1.png') center/cover no-repeat;
  opacity: 0.1;
  z-index: 0;
}

.header h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  position: relative;
  z-index: 1;
  text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.header p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.notice {
  background-color: var(--accent-color);
  color: white;
  padding: 10px 20px;
  border-radius: 4px;
  display: inline-block;
  margin-top: 2rem;
  font-weight: bold;
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
  position: relative;
  z-index: 1;
}

/* Navigation */
.nav {
  position: sticky;
  top: 0;
  background-color: var(--primary-color);
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0,0,0,0.2);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-link {
  color: white;
  text-decoration: none;
  font-weight: 500;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  transition: all 0.3s ease;
}

.nav-link:hover {
  background-color: rgba(255,255,255,0.1);
  transform: translateY(-2px);
}

/* Article Styles */
article {
  padding: 2rem 0;
}

article h2 {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--light-gray);
  position: relative;
}

article h2::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100px;
  height: 2px;
  background: var(--accent-color);
}

article section {
  margin-bottom: 3rem;
  background-color: white;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 6px rgba(0,0,0,0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

article section:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

article h3 {
  font-size: 1.5rem;
  color: var(--primary-color);
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
}

article h3::before {
  content: '';
  display: inline-block;
  width: 20px;
  height: 20px;
  background-color: var(--accent-color);
  margin-right: 10px;
  border-radius: 4px;
}

article p {
  margin-bottom: 1.5rem;
  font-size: 1.1rem;
}

/* Code Block Styles */
pre {
  background-color: #282c34;
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  overflow: auto;
  position: relative;
}

code {
  font-family: 'Courier New', monospace;
  color: #abb2bf;
  font-size: 0.9rem;
  line-height: 1.5;
}

pre::before {
  content: 'CSS';
  position: absolute;
  top: 0;
  left: 0;
  background-color: var(--accent-color);
  color: white;
  padding: 0.2rem 0.8rem;
  border-radius: 0 0 4px 0;
  font-size: 0.8rem;
  font-weight: bold;
}

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

.gallery-item {
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
  height: 300px;
}

.gallery-item:hover {
  transform: scale(1.03);
  box-shadow: 0 10px 20px rgba(0,0,0,0.2);
}

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

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

/* Footer */
.footer {
  background: var(--gradient-blue);
  color: white;
  padding: 3rem 0;
  text-align: center;
  margin-top: 3rem;
}

.footer p {
  margin-bottom: 1rem;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-top: 1.5rem;
}

.footer-link {
  color: white;
  text-decoration: none;
  transition: color 0.3s ease;
}

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

/* Responsive Adjustments */
@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    padding: 1rem;
  }
  
  .nav-links {
    margin-top: 1rem;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
  }
  
  article section {
    padding: 1.5rem;
  }
  
  .image-gallery {
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  }
}

@media (max-width: 480px) {
  .header h1 {
    font-size: 2rem;
  }
  
  .header p {
    font-size: 1rem;
  }
  
  article h2 {
    font-size: 1.5rem;
  }
  
  article h3 {
    font-size: 1.2rem;
  }
  
  .image-gallery {
    grid-template-columns: 1fr;
  }
}

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

.fade-in {
  animation: fadeIn 1s ease forwards;
}

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

/* Utility Classes */
.text-center { text-align: center; }
.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }
.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }