:root {
  --primary: rgba(74, 144, 226, 0.8);
  --secondary: rgba(142, 68, 173, 0.8);
  --accent: rgba(255, 111, 97, 0.8);
  --text: #2C3E50;
  --light: rgba(255, 255, 255, 0.8);
  --dark: rgba(31, 38, 135, 0.37);
  --success: #2ECC71;
}

@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@500;700&family=Open+Sans:wght@400;600&display=swap');

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

body {
  font-family: 'Open Sans', sans-serif;
  color: var(--text);
  background: linear-gradient(135deg, #f5f7fa 0%, #e4e8f0 100%);
  line-height: 1.6;
  overflow-x: hidden;
}

.header {
  position: relative;
  height: 80vh;
  max-height: 800px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 2rem;
  background: linear-gradient(135deg, rgba(74, 144, 226, 0.1) 0%, rgba(189, 195, 199, 0.1) 100%);
  overflow: hidden;
}

.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: -1;
}

.header h1 {
  font-family: 'Montserrat', sans-serif;
  font-size: 3.5rem;
  margin-bottom: 1.5rem;
  background: linear-gradient(45deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header p {
  max-width: 800px;
  font-size: 1.2rem;
  margin-bottom: 2rem;
  color: var(--text);
}

.note {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: rgba(255,255,255,0.9);
  padding: 10px 20px;
  border-radius: 50px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
  font-size: 0.9rem;
  z-index: 1000;
}

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

.nav {
  display: flex;
  justify-content: center;
  margin-bottom: 3rem;
  position: sticky;
  top: 0;
  background: rgba(255,255,255,0.9);
  backdrop-filter: blur(10px);
  padding: 1rem;
  z-index: 100;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.nav a {
  margin: 0 1.5rem;
  text-decoration: none;
  color: var(--text);
  font-family: 'Montserrat', sans-serif;
  font-weight: 500;
  position: relative;
  transition: all 0.3s ease;
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.3s ease;
}

.nav a:hover {
  color: var(--primary);
}

.nav a:hover::after {
  width: 100%;
}

article {
  background: rgba(255,255,255,0.7);
  backdrop-filter: blur(5px);
  border-radius: 20px;
  padding: 3rem;
  margin-bottom: 3rem;
  box-shadow: 0 8px 32px rgba(31, 38, 135, 0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

article:hover {
  transform: translateY(-5px);
  box-shadow: 0 12px 40px rgba(31, 38, 135, 0.2);
}

article h2 {
  font-family: 'Montserrat', sans-serif;
  font-size: 2.2rem;
  margin-bottom: 1.5rem;
  color: var(--primary);
  position: relative;
  padding-bottom: 0.5rem;
}

article h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 80px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
}

article h3 {
  font-family: 'Montserrat', sans-serif;
  font-size: 1.8rem;
  margin: 2rem 0 1rem;
  color: var(--secondary);
}

article p {
  margin-bottom: 1.5rem;
  font-size: 1.1rem;
  line-height: 1.8;
}

pre {
  background: rgba(0,0,0,0.05);
  border-radius: 10px;
  padding: 1.5rem;
  margin: 1.5rem 0;
  overflow: auto;
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  position: relative;
}

pre::before {
  content: 'CSS';
  position: absolute;
  top: 0;
  left: 0;
  background: var(--primary);
  color: white;
  padding: 0.2rem 0.8rem;
  border-radius: 0 0 10px 0;
  font-size: 0.8rem;
  font-family: 'Montserrat', sans-serif;
}

code {
  font-family: 'Courier New', monospace;
  background: rgba(0,0,0,0.05);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  font-size: 0.9rem;
}

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

.image-card {
  background: white;
  border-radius: 15px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
}

.image-card:hover {
  transform: translateY(-10px);
  box-shadow: 0 15px 30px rgba(0,0,0,0.2);
}

.image-card img {
  width: 100%;
  height: 300px;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.image-card:hover img {
  transform: scale(1.05);
}

.table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  background: rgba(255,255,255,0.7);
  backdrop-filter: blur(5px);
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.table th {
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  color: white;
  padding: 1rem;
  text-align: left;
}

.table td {
  padding: 1rem;
  border-bottom: 1px solid rgba(0,0,0,0.05);
}

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

.table tr:nth-child(even) {
  background: rgba(0,0,0,0.02);
}

.footer {
  text-align: center;
  padding: 2rem;
  margin-top: 3rem;
  background: rgba(255,255,255,0.7);
  backdrop-filter: blur(5px);
  border-radius: 20px;
}

@media (max-width: 768px) {
  .header h1 {
    font-size: 2.5rem;
  }
  
  .nav {
    flex-wrap: wrap;
  }
  
  .nav a {
    margin: 0.5rem;
  }
  
  article {
    padding: 2rem 1.5rem;
  }
  
  .image-grid {
    grid-template-columns: 1fr;
  }
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-20px);
  }
}

.floating {
  animation: float 6s ease-in-out infinite;
}