:root {
  --primary: #032B44;
  --secondary: #1E90FF;
  --accent: #FFA500;
  --bg: #F5F7FA;
  --text: #333333;
  --light: #FFFFFF;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
}

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

body {
  font-family: 'Helvetica Neue', Arial, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  padding-top: 80px;
}

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

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: var(--light);
  padding: 20px 0;
  z-index: 1000;
  box-shadow: var(--shadow);
}

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: 24px;
  font-weight: bold;
  letter-spacing: 1px;
}

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

.nav-links a {
  color: var(--light);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

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

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

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

.hero {
  padding: 80px 0;
  text-align: center;
  background: linear-gradient(rgba(255,255,255,0.9), rgba(255,255,255,0.9)), 
              url('https://images.gptkong.com/demo/sample1.png');
  background-size: cover;
  background-position: center;
  border-radius: 16px;
  margin-bottom: 60px;
  box-shadow: var(--shadow);
}

.hero h1 {
  font-size: 42px;
  margin-bottom: 20px;
  color: var(--primary);
  text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.hero p {
  font-size: 18px;
  max-width: 700px;
  margin: 0 auto 30px;
  color: var(--text);
}

.notice {
  background: var(--light);
  padding: 15px;
  border-radius: 8px;
  display: inline-block;
  font-size: 14px;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
  color: var(--primary);
}

.content {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 40px;
  margin-bottom: 60px;
}

.main-content {
  background: var(--light);
  padding: 40px;
  border-radius: 16px;
  box-shadow: var(--shadow);
}

.sidebar {
  background: var(--light);
  padding: 30px;
  border-radius: 16px;
  box-shadow: var(--shadow);
  align-self: start;
  position: sticky;
  top: 100px;
}

.article {
  margin-bottom: 50px;
}

.article h2 {
  font-size: 28px;
  color: var(--primary);
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--secondary);
}

.article h3 {
  font-size: 22px;
  color: var(--secondary);
  margin: 30px 0 15px;
}

.article p {
  margin-bottom: 20px;
  font-size: 16px;
}

.code-block {
  background: #282c34;
  color: #abb2bf;
  padding: 20px;
  border-radius: 8px;
  margin: 20px 0;
  overflow-x: auto;
  font-family: 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.5;
  position: relative;
}

.code-block::before {
  content: 'CSS';
  position: absolute;
  top: 0;
  left: 0;
  background: var(--secondary);
  color: var(--light);
  padding: 2px 10px;
  border-radius: 0 0 4px 0;
  font-size: 12px;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin: 30px 0;
}

.gallery img {
  width: 100%;
  height: auto;
  border-radius: 8px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

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

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 30px;
}

.tag {
  background: var(--secondary);
  color: var(--light);
  padding: 5px 12px;
  border-radius: 20px;
  font-size: 12px;
  transition: all 0.3s ease;
}

.tag:hover {
  background: var(--accent);
  transform: scale(1.05);
}

.footer {
  background: var(--primary);
  color: var(--light);
  padding: 40px 0;
  text-align: center;
  margin-top: 60px;
}

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

.social-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-top: 20px;
}

.social-links a {
  color: var(--light);
  font-size: 20px;
  transition: color 0.3s ease;
}

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

@media (max-width: 992px) {
  .content {
    grid-template-columns: 1fr;
  }
  
  .sidebar {
    position: static;
  }
  
  .gallery {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav {
    flex-direction: column;
    gap: 20px;
  }
  
  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .hero h1 {
    font-size: 32px;
  }
  
  .gallery {
    grid-template-columns: 1fr;
  }
}

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

.animate {
  animation: fadeIn 0.8s ease forwards;
}

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