:root {
  --primary: #3498db;
  --secondary: #f39c12;
  --accent: #e74c3c;
  --light: #ecf0f1;
  --dark: #2c3e50;
  --gradient-blue: linear-gradient(135deg, #3498db, #2980b9);
  --gradient-orange: linear-gradient(135deg, #f39c12, #e67e22);
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  --radius: 12px;
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
  font-family: 'Roboto', sans-serif;
  line-height: 1.8;
  color: var(--dark);
  background: linear-gradient(145deg, #f9f9f9, #ffffff);
  min-height: 100%;
  overflow-x: hidden;
}

.header {
  position: relative;
  height: 400px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-blue);
  color: white;
  text-align: center;
  padding: 0 20px;
  overflow: hidden;
  margin-bottom: 60px;
}

.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: 0.15;
}

.header h1 {
  font-size: 3.5rem;
  margin-bottom: 20px;
  position: relative;
  z-index: 2;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
  animation: fadeInDown 1s ease-out;
}

.header p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto 30px;
  position: relative;
  z-index: 2;
  animation: fadeInUp 1s ease-out 0.3s both;
}

.notice {
  background: rgba(255, 255, 255, 0.9);
  color: var(--dark);
  padding: 15px 25px;
  border-radius: var(--radius);
  display: inline-block;
  font-size: 0.9rem;
  box-shadow: var(--shadow);
  position: relative;
  z-index: 2;
  animation: fadeIn 1s ease-out 0.6s both;
}

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

.article {
  background: white;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 50px;
  margin-bottom: 60px;
  position: relative;
  overflow: hidden;
}

.article::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 5px;
  height: 100%;
  background: var(--gradient-orange);
}

.article h2 {
  font-size: 2.2rem;
  margin-bottom: 30px;
  color: var(--primary);
  position: relative;
}

.article h2::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 0;
  width: 80px;
  height: 4px;
  background: var(--gradient-orange);
  border-radius: 2px;
}

.article h3 {
  font-size: 1.8rem;
  margin: 40px 0 20px;
  color: var(--secondary);
}

.article p {
  margin-bottom: 25px;
  font-size: 1.1rem;
}

.code-container {
  background: #282c34;
  border-radius: var(--radius);
  padding: 20px;
  margin: 30px 0;
  position: relative;
  overflow: hidden;
}

.code-container::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 40px;
  background: rgba(0, 0, 0, 0.2);
}

.code-container pre {
  margin: 0;
  overflow: auto;
}

.code-container code {
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  color: #abb2bf;
  line-height: 1.6;
  display: block;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 25px;
  margin: 40px 0;
}

.gallery img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: var(--transition);
}

.gallery img:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.table-container {
  overflow-x: auto;
  margin: 40px 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: white;
  box-shadow: var(--shadow);
  border-radius: var(--radius);
  overflow: hidden;
}

th, td {
  padding: 15px;
  text-align: left;
  border-bottom: 1px solid #eee;
}

th {
  background: var(--primary);
  color: white;
  font-weight: 500;
}

tr:nth-child(even) {
  background: #f9f9f9;
}

tr:hover {
  background: #f1f1f1;
}

.footer {
  text-align: center;
  padding: 30px;
  background: var(--dark);
  color: white;
  margin-top: 60px;
}

.footer p {
  font-size: 0.9rem;
  opacity: 0.8;
}

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

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

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

@media (max-width: 768px) {
  .header h1 {
    font-size: 2.5rem;
  }
  
  .article {
    padding: 30px;
  }
  
  .article h2 {
    font-size: 1.8rem;
  }
  
  .article h3 {
    font-size: 1.5rem;
  }
}

@media (max-width: 480px) {
  .header {
    height: 300px;
  }
  
  .header h1 {
    font-size: 2rem;
  }
  
  .article {
    padding: 20px;
  }
  
  .gallery {
    grid-template-columns: 1fr;
  }
}