:root {
  --primary: #0D6EFD;
  --primary-light: #1976D2;
  --bg: #F8FAFC;
  --text: #1E293B;
  --accent: #FFD700;
  --card-bg: #FFFFFF;
  --border: #E5E7EB;
}

* {
  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: 0;
  margin: 0;
  overflow-x: hidden;
}

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

.header {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  padding: 80px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
  margin-bottom: 60px;
}

.header::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(248,250,252,0.3), transparent 70%);
  transform: translate(-50%, -50%);
  border-radius: 50%;
}

.header h1 {
  font-size: 2.5rem;
  margin-bottom: 20px;
  position: relative;
  z-index: 2;
  text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.header p {
  max-width: 700px;
  margin: 0 auto;
  position: relative;
  z-index: 2;
  font-size: 1.1rem;
  opacity: 0.9;
}

.notice {
  background: var(--card-bg);
  padding: 15px;
  border-radius: 8px;
  margin: 30px auto;
  max-width: 800px;
  text-align: center;
  box-shadow: 0 4px 6px rgba(0,0,0,0.05);
  border-left: 4px solid var(--accent);
}

.article-container {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 40px;
  margin: 40px 0;
}

@media (max-width: 900px) {
  .article-container {
    grid-template-columns: 1fr;
  }
}

article {
  background: var(--card-bg);
  padding: 40px;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

article h2 {
  color: var(--primary);
  margin-bottom: 25px;
  font-size: 1.8rem;
  position: relative;
  padding-bottom: 10px;
}

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

article h3 {
  color: var(--primary-light);
  margin: 30px 0 15px;
  font-size: 1.4rem;
}

article h4 {
  color: var(--text);
  margin: 25px 0 10px;
  font-size: 1.2rem;
}

article p {
  margin-bottom: 20px;
  font-size: 1.05rem;
}

article table {
  width: 100%;
  border-collapse: collapse;
  margin: 25px 0;
  box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

article table th {
  background: var(--primary-light);
  color: white;
  padding: 12px;
  text-align: left;
}

article table td {
  padding: 12px;
  border-bottom: 1px solid var(--border);
}

article table tr:nth-child(even) {
  background: rgba(248,250,252,0.5);
}

pre {
  background: #2D3748;
  color: #E2E8F0;
  padding: 20px;
  border-radius: 8px;
  overflow-x: auto;
  margin: 20px 0;
  font-family: 'Courier New', monospace;
  font-size: 0.95rem;
  line-height: 1.5;
  box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

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

.sidebar {
  position: sticky;
  top: 20px;
  align-self: start;
}

.nav-menu {
  background: var(--card-bg);
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}

.nav-menu h3 {
  color: var(--primary);
  margin-bottom: 15px;
  font-size: 1.2rem;
}

.nav-menu ul {
  list-style: none;
}

.nav-menu li {
  margin-bottom: 10px;
}

.nav-menu a {
  color: var(--text);
  text-decoration: none;
  display: block;
  padding: 8px 0;
  transition: color 0.2s;
  position: relative;
}

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

.nav-menu a::before {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.3s;
}

.nav-menu a:hover::before {
  width: 20px;
}

.image-gallery {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 15px;
  margin-top: 30px;
}

@media (max-width: 768px) {
  .image-gallery {
    grid-template-columns: repeat(2, 1fr);
  }
}

.gallery-image {
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
  transition: transform 0.3s, box-shadow 0.3s;
}

.gallery-image:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0,0,0,0.15);
}

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

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

.footer {
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: white;
  text-align: center;
  padding: 30px 0;
  margin-top: 60px;
}

.footer p {
  opacity: 0.8;
}

.highlight {
  background: rgba(255,215,0,0.2);
  padding: 2px 4px;
  border-radius: 3px;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.floating {
  animation: float 3s ease-in-out infinite;
}

@media (max-width: 600px) {
  article {
    padding: 25px;
  }
  
  .header h1 {
    font-size: 2rem;
  }
  
  .image-gallery {
    grid-template-columns: 1fr;
  }
}