:root {
  --primary: #2a3b4d;
  --secondary: #4a6b8a;
  --accent: #ff7e33;
  --light: #f8f9fa;
  --dark: #1a1a2e;
  --gradient: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
}

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

body {
  font-family: 'Roboto', sans-serif;
  line-height: 1.6;
  color: var(--dark);
  background: linear-gradient(145deg, #f0f4f8 0%, #e6ebf5 100%);
  min-height: 100%;
  overflow-x: hidden;
}

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

header {
  background: rgba(255,255,255,0.95);
  box-shadow: 0 2px 15px rgba(0,0,0,0.1);
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 15px 0;
}

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

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

.logo span {
  color: var(--accent);
}

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

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

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  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;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50px;
  left: -50px;
  width: 200px;
  height: 200px;
  background: radial-gradient(circle, rgba(255,126,51,0.2) 0%, rgba(255,126,51,0) 70%);
  z-index: -1;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -50px;
  right: -50px;
  width: 300px;
  height: 300px;
  background: radial-gradient(circle, rgba(42,59,77,0.1) 0%, rgba(42,59,77,0) 70%);
  z-index: -1;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 20px;
  color: var(--primary);
  position: relative;
  display: inline-block;
}

.hero h1::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background: var(--accent);
  border-radius: 2px;
}

.hero p {
  font-size: 1.2rem;
  color: var(--secondary);
  max-width: 800px;
  margin: 0 auto 40px;
}

.notice {
  background: rgba(255,126,51,0.1);
  padding: 15px;
  border-radius: 8px;
  border-left: 4px solid var(--accent);
  margin: 40px 0;
  font-weight: 500;
}

.notice span {
  color: var(--accent);
  font-weight: 700;
}

.content-section {
  padding: 60px 0;
  position: relative;
}

.content-section:nth-child(even) {
  background: rgba(255,255,255,0.7);
}

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

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 3px;
  background: var(--accent);
}

.grid-layout {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin-bottom: 40px;
}

.card {
  background: white;
  border-radius: 10px;
  overflow: hidden;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 15px 30px rgba(0,0,0,0.15);
}

.card-img {
  height: 200px;
  overflow: hidden;
}

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

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

.card-body {
  padding: 20px;
}

.card-title {
  font-size: 1.3rem;
  margin-bottom: 10px;
  color: var(--primary);
}

.card-text {
  color: var(--secondary);
  margin-bottom: 15px;
}

.code-block {
  background: #2a3b4d;
  color: #f8f9fa;
  padding: 20px;
  border-radius: 8px;
  margin: 20px 0;
  overflow-x: auto;
  font-family: 'Courier New', monospace;
  position: relative;
}

.code-block::before {
  content: 'CSS';
  position: absolute;
  top: 0;
  right: 0;
  background: var(--accent);
  color: white;
  padding: 3px 10px;
  border-radius: 0 0 0 8px;
  font-size: 0.8rem;
}

pre {
  margin: 0;
  white-space: pre-wrap;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
  background: white;
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  border-radius: 8px;
  overflow: hidden;
}

th, td {
  padding: 12px 15px;
  text-align: left;
  border-bottom: 1px solid #e0e0e0;
}

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

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

tr:hover {
  background: rgba(255,126,51,0.05);
}

footer {
  background: var(--primary);
  color: white;
  padding: 40px 0;
  text-align: center;
}

.footer-content {
  max-width: 800px;
  margin: 0 auto;
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin: 20px 0;
}

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

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

@media (max-width: 768px) {
  .nav-links {
    gap: 15px;
  }
  
  .hero h1 {
    font-size: 2.2rem;
  }
  
  .hero p {
    font-size: 1rem;
  }
  
  .section-title {
    font-size: 1.6rem;
  }
}

@media (max-width: 576px) {
  .nav-container {
    flex-direction: column;
    gap: 15px;
  }
  
  .hero {
    padding: 60px 0;
  }
  
  .content-section {
    padding: 40px 0;
  }
}

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

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