:root {
  --primary-color: #1A365D;
  --background-color: #F2F4F8;
  --accent-blue: #00BFFF;
  --accent-green: #34C759;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --text-color: #333;
  --light-gray: #E5E7EB;
}

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

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

.header {
  position: relative;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 5%;
  background: linear-gradient(135deg, var(--primary-color), #0F2B4D);
  color: white;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  z-index: 100;
}

.header::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 0;
  width: 100%;
  height: 10px;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-green));
  opacity: 0.7;
}

.nav {
  display: flex;
  gap: 30px;
}

.nav a {
  color: white;
  text-decoration: none;
  font-weight: 500;
  position: relative;
  padding: 5px 0;
  transition: all 0.3s ease;
}

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

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

.banner {
  position: relative;
  height: 400px;
  background: linear-gradient(135deg, rgba(26, 54, 93, 0.9), rgba(15, 43, 77, 0.9)), 
              url('https://images.gptkong.com/demo/sample1.png');
  background-size: cover;
  background-position: center;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  color: white;
  padding: 0 20px;
  margin-bottom: 60px;
  clip-path: polygon(0 0, 100% 0, 100% 85%, 0 100%);
}

.banner h1 {
  font-size: 2.8rem;
  margin-bottom: 20px;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.banner p {
  font-size: 1.2rem;
  max-width: 700px;
  margin-bottom: 30px;
}

.notice {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: white;
  padding: 15px 20px;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  z-index: 1000;
  animation: slideIn 0.5s ease-out;
}

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.main-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 5%;
}

article {
  background: white;
  border-radius: 12px;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  padding: 40px;
  margin-bottom: 60px;
  position: relative;
  overflow: hidden;
}

article::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 5px;
  height: 100%;
  background: linear-gradient(to bottom, var(--accent-blue), var(--accent-green));
}

article h2 {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 30px;
  position: relative;
  padding-bottom: 15px;
}

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

article h3 {
  font-size: 1.5rem;
  color: var(--primary-color);
  margin: 30px 0 20px;
  position: relative;
  padding-left: 15px;
}

article h3::before {
  content: '';
  position: absolute;
  left: 0;
  top: 5px;
  height: 70%;
  width: 4px;
  background: var(--accent-blue);
  border-radius: 2px;
}

article p {
  margin-bottom: 20px;
  font-size: 1.1rem;
  line-height: 1.7;
}

article span {
  color: var(--accent-blue);
  font-weight: 500;
}

.code-container {
  position: relative;
  margin: 30px 0;
  border-radius: 8px;
  overflow: hidden;
}

pre {
  background: #1E1E1E;
  color: #D4D4D4;
  padding: 20px;
  border-radius: 8px;
  overflow-x: auto;
  font-family: 'Consolas', 'Monaco', monospace;
  font-size: 0.9rem;
  line-height: 1.5;
  tab-size: 2;
}

code {
  font-family: 'Consolas', 'Monaco', monospace;
}

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

.image-card {
  position: relative;
  border-radius: 12px;
  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 12px 24px rgba(0, 0, 0, 0.15);
}

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

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

.image-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 40%;
  background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 30px 0;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  border-radius: 8px;
  overflow: hidden;
}

th, td {
  padding: 15px;
  text-align: left;
  border-bottom: 1px solid var(--light-gray);
}

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

tr:nth-child(even) {
  background-color: rgba(242, 244, 248, 0.5);
}

tr:hover {
  background-color: rgba(0, 191, 255, 0.05);
}

.footer {
  background: linear-gradient(135deg, var(--primary-color), #0F2B4D);
  color: white;
  padding: 40px 5%;
  text-align: center;
  margin-top: 60px;
}

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

.footer-links {
  display: flex;
  justify-content: center;
  gap: 30px;
  margin-bottom: 30px;
}

.footer-links a {
  color: white;
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer-links a:hover {
  color: var(--accent-blue);
}

@media (max-width: 768px) {
  .header {
    padding: 0 20px;
    height: 70px;
  }
  
  .nav {
    gap: 15px;
  }
  
  .banner {
    height: 300px;
    padding: 0 20px;
  }
  
  .banner h1 {
    font-size: 2rem;
  }
  
  .banner p {
    font-size: 1rem;
  }
  
  article {
    padding: 30px 20px;
  }
  
  article h2 {
    font-size: 1.8rem;
  }
  
  article h3 {
    font-size: 1.3rem;
  }
  
  .image-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-links {
    flex-direction: column;
    gap: 15px;
  }
}

@media (max-width: 480px) {
  .header {
    flex-direction: column;
    height: auto;
    padding: 15px;
  }
  
  .nav {
    margin-top: 15px;
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .banner {
    height: 250px;
    clip-path: polygon(0 0, 100% 0, 100% 90%, 0 100%);
  }
  
  .banner h1 {
    font-size: 1.5rem;
  }
  
  article {
    padding: 20px 15px;
  }
  
  article h2 {
    font-size: 1.5rem;
  }
  
  pre {
    padding: 15px;
    font-size: 0.8rem;
  }
}