:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f7fafc;
  --bg-tertiary: #edf2f7;
  --text-primary: #1a202c;
  --text-secondary: #4a5568;
  --text-tertiary: #718096;
  --border: #e2e8f0;
  --accent: #3182ce;
  --accent-light: #63b3ed;
  --accent-dark: #2c5aa0;
  --success: #38a169;
  --warning: #d69e2e;
  --error: #e53e3e;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,.07);
  --shadow-lg: 0 10px 15px rgba(0,0,0,.1);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg-primary: #1a202c;
    --bg-secondary: #2d3748;
    --bg-tertiary: #4a5568;
    --text-primary: #f7fafc;
    --text-secondary: #e2e8f0;
    --text-tertiary: #cbd5e0;
    --border: #4a5568;
  }
}

:root[data-theme="dark"] {
  --bg-primary: #1a202c;
  --bg-secondary: #2d3748;
  --bg-tertiary: #4a5568;
  --text-primary: #f7fafc;
  --text-secondary: #e2e8f0;
  --text-tertiary: #cbd5e0;
  --border: #4a5568;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  line-height: 1.6;
  letter-spacing: 0.3px;
  transition: var(--transition);
}

h1 {
  color: var(--text-primary);
  font-size: 2.5rem;
  font-weight: 700;
  margin: 0 0 16px 0;
  letter-spacing: -1px;
  line-height: 1.2;
}

h2 {
  color: var(--text-primary);
  font-size: 1.875rem;
  font-weight: 700;
  border-bottom: 3px solid var(--accent);
  padding-bottom: 12px;
  margin: 2rem 0 1.5rem 0;
  letter-spacing: -0.5px;
}

h3 {
  color: var(--accent);
  font-size: 1.25rem;
  font-weight: 600;
  margin: 1.5rem 0 1rem 0;
}

.info {
  color: var(--text-secondary);
  font-size: 15px;
  margin: 12px 0;
  line-height: 1.7;
}

.info a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition);
  border-bottom: 1px solid transparent;
}

.info a:hover {
  color: var(--accent-dark);
  border-bottom-color: var(--accent);
}

code {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  padding: 4px 8px;
  border-radius: 4px;
  font-family: "SFMono-Regular", "Courier New", monospace;
  font-size: 14px;
  word-break: break-all;
}

pre {
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  padding: 20px;
  border-radius: 8px;
  overflow-x: auto;
  font-family: "SFMono-Regular", "Courier New", monospace;
  font-size: 13px;
  line-height: 1.5;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border);
  margin: 1.5rem 0;
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
  font-size: inherit;
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 20px;
}

header {
  background: linear-gradient(135deg, #3182ce 0%, #63b3ed 100%);
  color: white;
  padding: 80px 20px;
  box-shadow: var(--shadow-lg);
  margin-bottom: 40px;
  position: relative;
  overflow: hidden;
}

header::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -10%;
  width: 400px;
  height: 400px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  z-index: 0;
}

header::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -5%;
  width: 300px;
  height: 300px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 50%;
  z-index: 0;
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

header h1 {
  margin-bottom: 16px;
  color: white;
  font-size: 3rem;
  font-weight: 800;
  letter-spacing: -1.5px;
  line-height: 1.1;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.header-subtitle {
  color: rgba(255, 255, 255, 0.95);
  font-size: 18px;
  line-height: 1.8;
  margin: 0;
  font-weight: 300;
  letter-spacing: 0.2px;
}

footer {
  background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
  border-top: 2px solid var(--border);
  padding: 60px 20px 40px;
  margin-top: 100px;
  text-align: center;
}

footer p {
  color: var(--text-secondary);
  font-size: 14px;
  margin: 12px 0;
  line-height: 1.7;
  font-weight: 500;
  letter-spacing: 0.2px;
}

footer a {
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  transition: var(--transition);
  border-bottom: 2px solid transparent;
  display: inline-block;
  padding-bottom: 2px;
}

footer a:hover {
  color: var(--accent-dark);
  border-bottom-color: var(--accent);
  transform: translateY(-2px);
}

.footer-links {
  display: flex;
  justify-content: center;
  gap: 2.5rem;
  margin: 30px 0 0;
  flex-wrap: wrap;
  padding: 30px 0 0;
  border-top: 1px solid var(--border);
}

.footer-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
}

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

@media (max-width: 768px) {
  h1 {
    font-size: 1.875rem;
  }
  h2 {
    font-size: 1.5rem;
  }
  main {
    padding: 20px;
  }
  header {
    padding: 50px 20px;
    margin-bottom: 25px;
  }
  header h1 {
    font-size: 2rem;
    margin-bottom: 12px;
  }
  .header-subtitle {
    font-size: 15px;
  }
  footer {
    padding: 40px 20px 30px;
    margin-top: 60px;
  }
  footer p {
    font-size: 13px;
  }
  .footer-links {
    gap: 1.5rem;
    margin-top: 20px;
    padding-top: 20px;
  }
}