:root {
  --primary-color: #1A237E;
  --secondary-color: #E0E0E0;
  --accent-color: #00BCD4;
  --background-color: #FFFFFF;
  --text-color: #212121;
  --light-text: #757575;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --border-radius: 8px;
  --transition: all 0.3s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Roboto', 'Helvetica Neue', Arial, sans-serif;
}

body {
  background: linear-gradient(135deg, #f5f7fa 0%, #e4e8f0 100%);
  color: var(--text-color);
  line-height: 1.6;
  padding-top: 80px;
  min-height: 100%;
  overflow-x: hidden;
}

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

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: linear-gradient(90deg, var(--primary-color), #283593);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  padding: 15px 0;
}

.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 20px;
}

.logo {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--background-color);
  text-decoration: none;
  display: flex;
  align-items: center;
}

.logo-icon {
  margin-right: 10px;
  font-size: 2rem;
}

.nav-links {
  display: flex;
  list-style: none;
}

.nav-links li {
  margin-left: 30px;
}

.nav-links a {
  color: var(--secondary-color);
  text-decoration: none;
  font-weight: 500;
  font-size: 1.1rem;
  transition: var(--transition);
  position: relative;
  padding: 5px 0;
}

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

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--accent-color);
  transition: var(--transition);
}

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

.hero {
  padding: 80px 0;
  text-align: center;
  background: linear-gradient(rgba(26, 35, 126, 0.8), rgba(26, 35, 126, 0.6)), url('https://images.gptkong.com/demo/sample1.png');
  background-size: cover;
  background-position: center;
  color: var(--background-color);
  border-radius: var(--border-radius);
  margin-bottom: 40px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 20px;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.hero p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto 30px;
}

.notice {
  background-color: rgba(255, 255, 255, 0.2);
  padding: 15px;
  border-radius: var(--border-radius);
  display: inline-block;
  margin-top: 20px;
  backdrop-filter: blur(5px);
}

article {
  background-color: var(--background-color);
  border-radius: var(--border-radius);
  padding: 40px;
  box-shadow: 0 5px 15px var(--shadow-color);
  margin-bottom: 40px;
}

article h2 {
  color: var(--primary-color);
  font-size: 2.2rem;
  margin-bottom: 30px;
  position: relative;
  padding-bottom: 15px;
}

article h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 80px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
  border-radius: 2px;
}

article h3 {
  color: var(--primary-color);
  font-size: 1.8rem;
  margin: 30px 0 20px;
}

article p {
  margin-bottom: 20px;
  font-size: 1.1rem;
  line-height: 1.8;
}

pre {
  background: #f8f9fa;
  border-radius: var(--border-radius);
  padding: 20px;
  margin: 20px 0;
  overflow-x: auto;
  box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.05);
  border-left: 4px solid var(--accent-color);
}

code {
  font-family: 'Courier New', monospace;
  color: #d63384;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 25px 0;
  box-shadow: 0 0 20px rgba(0, 0, 0, 0.1);
  border-radius: var(--border-radius);
  overflow: hidden;
}

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

th {
  background-color: var(--primary-color);
  color: var(--background-color);
  font-weight: 600;
}

tr:nth-child(even) {
  background-color: #f8f9fa;
}

tr:hover {
  background-color: #f1f3f5;
}

.image-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
  margin: 30px 0;
}

.gallery-item {
  position: relative;
  overflow: hidden;
  border-radius: var(--border-radius);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
  transition: var(--transition);
}

.gallery-item:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

.gallery-item img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  transition: var(--transition);
}

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

.button {
  display: inline-block;
  background: linear-gradient(45deg, var(--primary-color), #3949ab);
  color: var(--background-color);
  padding: 12px 30px;
  border-radius: 50px;
  text-decoration: none;
  font-weight: 600;
  margin: 10px 0;
  transition: var(--transition);
  box-shadow: 0 4px 15px rgba(26, 35, 126, 0.3);
}

.button:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(26, 35, 126, 0.4);
  background: linear-gradient(45deg, #283593, #3949ab);
}

.footer {
  background: linear-gradient(90deg, var(--primary-color), #283593);
  color: var(--background-color);
  padding: 40px 0;
  text-align: center;
  margin-top: 60px;
}

.footer p {
  margin-bottom: 20px;
}

.social-links {
  display: flex;
  justify-content: center;
  list-style: none;
  margin: 20px 0;
}

.social-links li {
  margin: 0 15px;
}

.social-links a {
  color: var(--background-color);
  font-size: 1.5rem;
  transition: var(--transition);
}

.social-links a:hover {
  color: var(--accent-color);
  transform: translateY(-3px);
}

@media (max-width: 768px) {
  .navbar {
    flex-direction: column;
    padding: 15px;
  }

  .nav-links {
    margin-top: 20px;
    flex-direction: column;
    align-items: center;
  }

  .nav-links li {
    margin: 10px 0;
  }

  .hero h1 {
    font-size: 2.2rem;
  }

  article {
    padding: 25px;
  }

  article h2 {
    font-size: 1.8rem;
  }

  article h3 {
    font-size: 1.5rem;
  }

  .image-gallery {
    grid-template-columns: 1fr;
  }
}

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

.fade-in {
  animation: fadeIn 0.8s ease forwards;
}

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