:root {
  --primary-color: #1E3A8A;
  --secondary-color: #4CAF50;
  --accent-color: #FF9800;
  --background-color: #FFFFFF;
  --light-gray: #F5F5F5;
  --dark-bg: #121212;
  --text-dark: #FFFFFF;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

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

body {
  background: linear-gradient(135deg, var(--background-color) 0%, var(--light-gray) 100%);
  color: var(--primary-color);
  line-height: 1.6;
  min-height: 100%;
  overflow-x: hidden;
}

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

.header {
  text-align: center;
  padding: 60px 0 40px;
  position: relative;
}

.header::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(45deg, 
    rgba(30, 58, 138, 0.1) 0%, 
    rgba(76, 175, 80, 0.1) 100%);
  z-index: -1;
  clip-path: polygon(0 0, 100% 0, 100% 80%, 0 100%);
}

.header h1 {
  font-size: 2.8rem;
  margin-bottom: 20px;
  background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.header p {
  font-size: 1.2rem;
  max-width: 800px;
  margin: 0 auto;
  color: #555;
}

.notice {
  background: rgba(255, 152, 0, 0.1);
  border-left: 4px solid var(--accent-color);
  padding: 15px;
  margin: 30px 0;
  border-radius: 0 8px 8px 0;
}

.notice p {
  color: var(--primary-color);
  font-weight: 500;
}

article {
  padding: 40px 0;
}

article h2 {
  font-size: 2rem;
  margin: 40px 0 20px;
  color: var(--primary-color);
  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-color), var(--secondary-color));
  border-radius: 3px;
}

article h3 {
  font-size: 1.5rem;
  margin: 30px 0 15px;
  color: var(--secondary-color);
}

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

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

.image-card {
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: all 0.3s ease;
  position: relative;
}

.image-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
}

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

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

pre {
  background: #f8f8f8;
  border-radius: 8px;
  padding: 20px;
  margin: 25px 0;
  overflow: auto;
  box-shadow: var(--shadow);
  border-left: 4px solid var(--secondary-color);
}

code {
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  color: #333;
}

.nav-tabs {
  display: flex;
  margin: 40px 0 20px;
  border-bottom: 1px solid #eee;
}

.nav-tabs a {
  padding: 12px 20px;
  margin-right: 10px;
  text-decoration: none;
  color: var(--primary-color);
  border-radius: 6px 6px 0 0;
  transition: all 0.3s ease;
  font-weight: 500;
}

.nav-tabs a.active {
  background: var(--primary-color);
  color: white;
}

.nav-tabs a:hover:not(.active) {
  background: rgba(30, 58, 138, 0.1);
}

.footer {
  text-align: center;
  padding: 40px 0;
  margin-top: 60px;
  background: linear-gradient(45deg, 
    rgba(30, 58, 138, 0.05) 0%, 
    rgba(76, 175, 80, 0.05) 100%);
  clip-path: polygon(0 20%, 100% 0, 100% 100%, 0 100%);
}

.footer p {
  color: #666;
  font-size: 0.9rem;
}

@media (max-width: 768px) {
  .header h1 {
    font-size: 2rem;
  }
  
  article h2 {
    font-size: 1.6rem;
  }
  
  .image-grid {
    grid-template-columns: 1fr;
  }
}

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

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