:root {
  --primary-color: #4B7BF9;
  --secondary-color: #3CD18E;
  --accent-color: #FACD6A;
  --bg-light: #ffffff;
  --bg-dark: #121212;
  --text-light: #333333;
  --text-dark: #ffffff;
  --gray-light: #f5f5f5;
  --gray-medium: #e0e0e0;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

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

body {
  font-family: 'Roboto', sans-serif;
  line-height: 1.6;
  color: var(--text-light);
  background: linear-gradient(135deg, var(--gray-light) 0%, var(--bg-light) 100%);
  min-height: 100%;
  overflow-x: hidden;
}

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

.header {
  background: var(--bg-light);
  box-shadow: var(--shadow);
  position: relative;
  z-index: 100;
  padding: 20px 0;
}

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

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
  text-decoration: none;
  display: flex;
  align-items: center;
}

.logo::before {
  content: "";
  display: inline-block;
  width: 30px;
  height: 30px;
  background: linear-gradient(45deg, var(--primary-color), var(--secondary-color));
  border-radius: 6px;
  margin-right: 10px;
}

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

.nav-link {
  color: var(--text-light);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
  position: relative;
}

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

.nav-link::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary-color);
  transition: var(--transition);
}

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

.hero {
  padding: 80px 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 50% 50%, rgba(75, 123, 249, 0.1) 0%, rgba(255, 255, 255, 0) 70%);
  z-index: -1;
}

.hero-title {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: 20px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-light);
  max-width: 700px;
  margin: 0 auto 40px;
}

.notice {
  background: rgba(75, 123, 249, 0.1);
  padding: 15px;
  border-radius: 8px;
  margin: 40px auto;
  max-width: 800px;
  text-align: center;
  border-left: 4px solid var(--primary-color);
}

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

.content {
  padding: 60px 0;
}

.section {
  margin-bottom: 80px;
  background: var(--bg-light);
  border-radius: 12px;
  padding: 40px;
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
}

.section::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 100px;
  height: 100px;
  background: linear-gradient(45deg, var(--primary-color), transparent);
  border-radius: 0 0 0 100%;
  z-index: 0;
}

.section-title {
  font-size: 2rem;
  margin-bottom: 30px;
  position: relative;
  z-index: 1;
}

.section-title::after {
  content: "";
  display: block;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
  margin-top: 10px;
  border-radius: 2px;
}

.section-content {
  position: relative;
  z-index: 1;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin: 40px 0;
}

.card {
  background: var(--bg-light);
  border-radius: 12px;
  padding: 30px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid var(--gray-medium);
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.card-title {
  font-size: 1.3rem;
  margin-bottom: 15px;
  color: var(--primary-color);
}

.card-image {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 8px;
  margin-bottom: 20px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

pre {
  background: #f8f8f8;
  border-radius: 8px;
  padding: 20px;
  overflow-x: auto;
  margin: 20px 0;
  border-left: 4px solid var(--primary-color);
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  line-height: 1.5;
}

code {
  background: rgba(75, 123, 249, 0.1);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'Courier New', monospace;
  font-size: 0.9rem;
  color: var(--primary-color);
}

.footer {
  background: var(--bg-dark);
  color: var(--text-dark);
  padding: 40px 0;
  text-align: center;
}

.footer-text {
  opacity: 0.8;
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.2rem;
  }
  
  .nav {
    gap: 15px;
  }
  
  .section {
    padding: 30px 20px;
  }
  
  .grid {
    grid-template-columns: 1fr;
  }
}

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

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

/* Theme toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
}

.toggle-icon {
  width: 24px;
  height: 24px;
}

/* Image decorations */
.decorative-image {
  border-radius: 12px;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
  transition: var(--transition);
  margin: 20px 0;
}

.decorative-image:hover {
  transform: scale(1.02);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.15);
}