:root {
  /* Common Variables */
  --font-main: 'Plus Jakarta Sans', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --max-width: 1200px;
  --header-height: 70px;
  --radius-md: 12px;
  --radius-lg: 16px;

  /* Light Theme */
  --bg-color: #f8f9fa;
  --secondary-bg: rgba(255, 255, 255, 0.8);
  --card-bg: rgba(255, 255, 255, 0.7);
  --text-primary: #1a1a1a;
  --text-secondary: #5f6368;
  --border-color: rgba(0, 0, 0, 0.05);
  --accent-color: #0066ff;
  --accent-hover: #0052cc;
  --surface-hover: rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 4px 6px rgba(0, 0, 0, 0.02);
  --shadow-md: 0 12px 24px rgba(0, 0, 0, 0.06);
  --glass-border: 1px solid rgba(255, 255, 255, 0.5);
  --backdrop-blur: blur(20px);
}

[data-theme="dark"] {
  --bg-color: #050505;
  --secondary-bg: rgba(20, 20, 20, 0.6);
  --card-bg: rgba(20, 20, 20, 0.6);
  --text-primary: #ffffff;
  --text-secondary: #a0a0a0;
  --border-color: rgba(255, 255, 255, 0.08);
  --accent-color: #00f0ff;
  --accent-hover: #00bcd4;
  --surface-hover: rgba(255, 255, 255, 0.05);
  --shadow-sm: 0 4px 6px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 12px 24px rgba(0, 0, 0, 0.5);
  --glass-border: 1px solid rgba(255, 255, 255, 0.08);
}

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

body {
  font-family: var(--font-main);
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.3s ease, color 0.3s ease;
  position: relative;
  overflow-x: hidden;
}

#bg-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  pointer-events: none;
}

a {
  color: var(--accent-color);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s;
}

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

/* Header */
header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(var(--bg-color), 0.6);
  backdrop-filter: var(--backdrop-blur);
  -webkit-backdrop-filter: var(--backdrop-blur);
  border-bottom: var(--glass-border);
  height: var(--header-height);
  display: flex;
  align-items: center;
  padding: 0 2rem;
}

/* ... (skipping unchanged header-inner .logo etc) ... */

/* Grid System */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.card {
  background: var(--card-bg);
  border: var(--glass-border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: all 0.3s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--accent-color);
  background: rgba(var(--card-bg), 0.8);
}

.header-inner {
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 800;
  font-size: 1.25rem;
  letter-spacing: -0.03em;
  color: var(--text-primary);
}

.theme-toggle {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 50%;
  transition: background-color 0.2s, color 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background-color: var(--surface-hover);
  color: var(--text-primary);
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 4rem 2rem 2rem;
  max-width: 900px;
  margin: 0 auto;
}

h1 {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 1rem;
  letter-spacing: -0.04em;
  color: var(--text-primary);
}

.subtitle {
  font-size: 1.5rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
  font-weight: 400;
  line-height: 1.4;
}

/* Hero Buttons */
.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin-top: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.5rem;
  border-radius: 50px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: all 0.2s ease;
  border: none;
  cursor: pointer;
}

.btn-primary {
  background-color: var(--accent-color);
  color: white;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: white;
}

.btn-secondary {
  background-color: var(--surface-hover);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background-color: var(--card-bg);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
  color: var(--text-primary);
}

/* Citation Box */
.citation-box {
  position: relative;
  background-color: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  text-align: left;
  overflow-x: auto;
}

.citation-box pre {
  margin: 0;
  font-family: 'SF Mono', 'Monaco', 'Consolas', monospace;
  font-size: 0.85rem;
  line-height: 1.5;
  white-space: pre-wrap;
  word-break: break-word;
}

.citation-box code {
  color: var(--text-secondary);
}

.copy-btn {
  position: absolute;
  top: 0.75rem;
  right: 0.75rem;
  background: var(--surface-hover);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 0.5rem;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.copy-btn:hover {
  background: var(--card-bg);
  color: var(--text-primary);
  border-color: var(--accent-color);
}

/* Main Content */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 2rem 2rem;
}

section {
  margin-bottom: 3rem;
}

h2 {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  letter-spacing: -0.03em;
  color: var(--text-primary);
  text-align: center;
}

.intro-text {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

/* Grid System */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
}

.card {
  background: var(--card-bg);
  border: var(--glass-border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: all 0.3s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--accent-color);
  background: rgba(var(--card-bg), 0.8);
}

.card h3 {
  margin-bottom: 0.75rem;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.card p {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* Figures */
.figure-container {
  background-color: var(--secondary-bg);
  padding: 2rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  margin-bottom: 2rem;
  text-align: center;
}

.figure-container img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  box-shadow: var(--shadow-sm);
}

.caption {
  margin-top: 1.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* Footer */
footer {
  border-top: 1px solid var(--border-color);
  padding: 4rem 2rem;
  text-align: center;
  background-color: var(--secondary-bg);
  color: var(--text-secondary);
}

.authors {
  margin-bottom: 1rem;
  font-weight: 500;
  color: var(--text-primary);
}

/* Mobile & Tablet Responsiveness */
@media (max-width: 768px) {

  /* Typography */
  h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
  }

  h2 {
    font-size: 1.75rem;
    margin-bottom: 1.25rem;
  }

  .subtitle {
    font-size: 1.15rem;
    line-height: 1.5;
  }

  /* Layout spacing */
  main {
    padding: 0 1.25rem 2rem;
  }

  section {
    margin-bottom: 3rem;
  }

  /* Hero section */
  .hero {
    padding: 3rem 1.25rem 2rem;
  }

  .hero-buttons {
    flex-direction: column;
    gap: 0.75rem;
  }

  /* Header */
  .header-inner {
    padding: 0 1rem;
  }

  .logo {
    font-size: 1.1rem;
  }

  /* Buttons */
  .btn {
    width: 100%;
    padding: 0.875rem 1.5rem;
    font-size: 1rem;
  }

  /* Cards */
  .card {
    padding: 1.5rem;
  }

  .card h3 {
    font-size: 1.15rem;
  }

  /* Grids - ensure proper stacking */
  .grid {
    grid-template-columns: 1fr !important;
    gap: 1.5rem;
  }

  /* Override inline styles for responsive behavior */
  .grid[style*="repeat(3, 1fr)"],
  .grid[style*="1fr 1fr"] {
    grid-template-columns: 1fr !important;
  }

  /* Intro text */
  .intro-text {
    font-size: 1.1rem;
    padding: 0 0.5rem;
  }

  /* Figure containers */
  .figure-container {
    padding: 1.25rem;
    margin-bottom: 1.5rem;
  }

  .figure-container img {
    border-radius: 6px;
  }

  .caption {
    font-size: 0.85rem;
    margin-top: 1rem;
  }

  /* Citation box */
  .citation-box {
    padding: 1rem;
    font-size: 0.8rem;
  }

  .copy-btn {
    top: 0.5rem;
    right: 0.5rem;
    padding: 0.4rem;
  }

  /* Footer */
  footer {
    padding: 3rem 1.25rem;
  }

  .authors {
    font-size: 0.95rem;
    line-height: 1.6;
  }

  .author-note {
    font-size: 0.75rem !important;
  }
}

/* Extra small screens (phones in portrait) */
@media (max-width: 480px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .hero {
    padding: 2.5rem 1rem 1.5rem;
  }

  main {
    padding: 0 1rem 1.5rem;
  }

  section {
    margin-bottom: 2.5rem;
  }

  .card {
    padding: 1.25rem;
  }

  .intro-text {
    font-size: 1rem;
  }
}