:root {
  --primary: #333333;
  --secondary: #00C6FF;
  --accent: #98FF98;
  --bg: #FFFFFF;
  --text: #333333;
  --light-gray: #F5F5F5;
  --medium-gray: #E0E0E0;
  --dark-gray: #666666;
}

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

body {
  font-family: 'Helvetica Neue', sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background-color: var(--bg);
  overflow-x: hidden;
}

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

.header {
  background: linear-gradient(135deg, var(--bg) 0%, var(--light-gray) 100%);
  padding: 60px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center right/contain;
  opacity: 0.1;
  z-index: 0;
}

.header h1 {
  font-size: 2.8em;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 20px;
  position: relative;
  z-index: 1;
  text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.header p {
  font-size: 1.2em;
  max-width: 800px;
  margin: 0 auto 30px;
  position: relative;
  z-index: 1;
}

.notice {
  background-color: var(--secondary);
  color: white;
  padding: 15px;
  border-radius: 8px;
  margin: 40px auto;
  max-width: 800px;
  text-align: center;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  position: relative;
  overflow: hidden;
}

.notice::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg, transparent 45%, rgba(255,255,255,0.3) 50%, transparent 55%);
  animation: shine 3s infinite;
  z-index: 0;
}

@keyframes shine {
  0% { transform: translateX(-100%) translateY(-100%) rotate(45deg); }
  100% { transform: translateX(100%) translateY(100%) rotate(45deg); }
}

.notice span {
  position: relative;
  z-index: 1;
}

article {
  padding: 40px 0;
}

article h2 {
  font-size: 2em;
  font-weight: 700;
  margin: 40px 0 20px;
  color: var(--primary);
  position: relative;
  padding-bottom: 10px;
}

article h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--secondary), var(--accent));
}

article h3 {
  font-size: 1.5em;
  font-weight: 600;
  margin: 30px 0 15px;
  color: var(--primary);
}

article p {
  margin-bottom: 20px;
  font-size: 1em;
  line-height: 1.7;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 25px 0;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
  border-radius: 8px;
  overflow: hidden;
}

table th {
  background-color: var(--secondary);
  color: white;
  padding: 12px 15px;
  text-align: left;
}

table td {
  padding: 12px 15px;
  border-bottom: 1px solid var(--medium-gray);
}

table tr:last-child td {
  border-bottom: none;
}

table tr:nth-child(even) {
  background-color: var(--light-gray);
}

pre {
  background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
  padding: 20px;
  border-radius: 8px;
  margin: 25px 0;
  overflow-x: auto;
  box-shadow: inset 0 1px 3px rgba(0,0,0,0.1);
  border-left: 4px solid var(--secondary);
}

code {
  font-family: 'Courier New', monospace;
  font-size: 0.9em;
  color: var(--primary);
}

.image-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
  margin: 40px 0;
}

.image-card {
  background: white;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.image-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.15);
}

.image-card img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 8px 8px 0 0;
}

.image-card .caption {
  padding: 15px;
  background: white;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 30px 0;
}

.nav-links a {
  display: inline-block;
  padding: 10px 15px;
  background-color: var(--light-gray);
  color: var(--primary);
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.3s ease;
  font-size: 0.9em;
}

.nav-links a:hover {
  background-color: var(--secondary);
  color: white;
}

.footer {
  background: linear-gradient(135deg, var(--primary) 0%, #222222 100%);
  color: white;
  padding: 40px 0;
  text-align: center;
  margin-top: 60px;
}

.footer p {
  margin-bottom: 10px;
}

@media (max-width: 768px) {
  .header h1 {
    font-size: 2em;
  }
  
  article h2 {
    font-size: 1.7em;
  }
  
  article h3 {
    font-size: 1.3em;
  }
  
  .image-grid {
    grid-template-columns: 1fr;
  }
}

/* Animation classes */
.animate-fade {
  animation: fadeIn 0.8s ease forwards;
}

.animate-slide {
  animation: slideUp 0.8s ease forwards;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from { 
    opacity: 0;
    transform: translateY(30px);
  }
  to { 
    opacity: 1;
    transform: translateY(0);
  }
}