:root {
  --primary: #002f6c;
  --secondary: #ffa500;
  --accent: #00b4d8;
  --bg-light: linear-gradient(135deg, #f8f9fa, #e9ecef);
  --text-dark: #212529;
  --text-light: #f8f9fa;
  --card-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

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

body {
  font-family: 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  line-height: 1.6;
  color: var(--text-dark);
  background: var(--bg-light);
  overflow-x: hidden;
}

.header-banner {
  background: linear-gradient(135deg, var(--primary), #001a3a);
  color: white;
  padding: 2rem;
  text-align: center;
  position: relative;
  overflow: hidden;
  margin-bottom: 3rem;
}

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

.notice {
  background: rgba(255,255,255,0.2);
  backdrop-filter: blur(10px);
  padding: 1rem;
  border-radius: 8px;
  margin: 2rem auto;
  max-width: 800px;
  text-align: center;
  border: 1px solid rgba(255,255,255,0.3);
}

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

.article-container {
  background: white;
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  padding: 3rem;
  margin-bottom: 3rem;
  position: relative;
  overflow: hidden;
}

.article-container::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 200px;
  height: 200px;
  background: radial-gradient(circle, var(--accent) 0%, transparent 70%);
  opacity: 0.1;
  z-index: 0;
}

h2 {
  color: var(--primary);
  font-size: 1.8rem;
  margin: 2rem 0 1.5rem;
  position: relative;
  padding-bottom: 0.5rem;
}

h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 3px;
  background: var(--secondary);
}

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

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

strong {
  color: var(--primary);
}

a {
  color: var(--secondary);
  text-decoration: none;
  transition: all 0.3s ease;
}

a:hover {
  color: var(--primary);
  text-decoration: underline;
}

pre {
  background: #f5f5f5;
  border-radius: 8px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  overflow-x: auto;
  position: relative;
  border-left: 4px solid var(--secondary);
}

code {
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  color: #333;
}

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

.gallery-item {
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--card-shadow);
  transition: transform 0.3s ease;
  position: relative;
}

.gallery-item:hover {
  transform: translateY(-5px);
}

.gallery-item img {
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.5s ease;
}

.gallery-item:hover img {
  transform: scale(1.05);
}

.nav-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 2rem 0;
}

.nav-tab {
  padding: 0.8rem 1.5rem;
  background: white;
  border-radius: 50px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.nav-tab:hover {
  background: var(--secondary);
  color: white;
  transform: translateY(-3px);
  box-shadow: 0 5px 15px rgba(255,165,0,0.3);
}

.footer {
  background: linear-gradient(135deg, var(--primary), #001a3a);
  color: white;
  padding: 3rem 2rem;
  text-align: center;
  margin-top: 3rem;
}

.footer p {
  max-width: 800px;
  margin: 0 auto 1rem;
}

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

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

.floating {
  animation: float 3s ease-in-out infinite;
}