:root {
  /* Base colors - dark theme for astrophysics aesthetic */
  --bg-primary: #0a0e1a;
  /* Deep space blue-black */
  --bg-secondary: #151b2e;
  --bg-elevated: #1f2937;

  /* Glassmorphism Variables */
  --bg-primary-glass: rgba(10, 14, 26, 0.65);
  --bg-secondary-glass: rgba(21, 27, 46, 0.65);
  --bg-elevated-glass: rgba(31, 41, 55, 0.65);
  --glass-border: 1px solid rgba(255, 255, 255, 0.08);
  --glass-blur: blur(12px);

  /* Text */
  --text-primary: #f3f4f6;
  --text-secondary: #9ca3af;

  /* Accent - subtle teal inspired by lensing color scales */
  --accent-primary: #06b6d4;
  /* Cyan */
  --accent-secondary: #8b5cf6;
  /* Purple */

  /* Status colors */
  --success: #10b981;
  --warning: #f59e0b;
  --info: #3b82f6;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
  margin: 0;
  padding: 0;
}

/* Custom Minimal Scrollbar */
html,
body {
  scrollbar-width: thin;
  scrollbar-color: var(--bg-elevated) var(--bg-primary);
}

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--bg-elevated);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-primary);
}

h1,
h2,
h3 {
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

p {
  color: var(--text-secondary);
  max-width: 70ch;
  /* Add auto-margins to ensure max-width paragraphs are centered inside centralized flex/block-containers */
  margin-left: auto;
  margin-right: auto;
}

code {
  font-family: 'Fira Code', 'Courier New', monospace;
  background: var(--bg-elevated);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
}

/* Layout & Glass Helpers */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
}

.glass-panel {
  background: var(--bg-elevated-glass);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: var(--glass-border);
  border-radius: 1rem;
  padding: 2rem;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

section {
  padding: 4rem 0;
  /* border-bottom: 1px solid var(--bg-elevated); REMOVED per user request */
}

/* Hero */
.hero {
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  z-index: 1;
  /* Above canvas */
  /* Remove solid radial background so 3D canvas shows through */
  background: transparent;
  padding: 2rem 1rem;
}

.hero .container {
  background: var(--bg-primary-glass);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  padding: 4rem 3rem;
  border-radius: 1.5rem;
  border: var(--glass-border);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.6);
  max-width: 800px;
  width: 100%;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  background: linear-gradient(to right, var(--accent-primary), var(--accent-secondary));
  -webkit-background_clip: text;
  background-clip: text;
  color: transparent;
}

.tagline {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  margin-left: auto;
  margin-right: auto;
}

.cta-buttons {
  display: flex;
  gap: 1rem;
  justify-content: center;
}

.btn-primary,
.btn-secondary {
  padding: 0.75rem 1.5rem;
  border-radius: 0.5rem;
  text-decoration: none;
  font-weight: 600;
  transition: all 0.2s;
}

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

.btn-primary:hover {
  filter: brightness(1.1);
  transform: translateY(-2px);
}

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

.btn-secondary:hover {
  border-color: var(--text-secondary);
}

/* Science Section Grid */
.science-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

/* Viewer Container */
.viewer-container {
  display: grid;
  grid-template-columns: 250px 1fr 300px;
  gap: 2rem;
  background: var(--bg-secondary-glass);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border-radius: 1rem;
  padding: 2rem;
  margin-top: 2rem;
  border: var(--glass-border);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

/* Sample Selector (Left) */
.sample-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-height: 600px;
  overflow-y: auto;
  padding-right: 0.5rem;
}

.sample-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem;
  background: var(--bg-elevated-glass);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  border-radius: 0.5rem;
  cursor: pointer;
  transition: all 0.2s;
  border: var(--glass-border);
}

.sample-item:hover {
  background: var(--bg-primary-glass);
  transform: translateX(4px);
}

.sample-item.active {
  border-color: var(--accent-primary);
  background: var(--bg-primary-glass);
}

.sample-thumb {
  width: 48px;
  height: 48px;
  border-radius: 4px;
  object-fit: cover;
  background: #000;
}

/* Main Display (Center) */
.main-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.canvas-wrapper {
  position: relative;
  width: 100%;
  max-width: 512px;
  aspect-ratio: 1 / 1;
  height: auto;
  background: #000;
  border-radius: 8px;
  box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
  overflow: hidden;
}

.canvas-wrapper img {
  width: 100%;
  height: 100%;
  image-rendering: pixelated;
  /* Crucial for low-res comparison */
}

.method-tabs {
  display: flex;
  gap: 0.5rem;
  background: var(--bg-elevated-glass);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  padding: 0.25rem;
  border-radius: 0.5rem;
  border: var(--glass-border);
  flex-wrap: wrap;
  justify-content: center;
}

.method-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.5rem 1rem;
  border-radius: 4px;
  cursor: pointer;
  font-weight: 500;
  transition: all 0.2s;
}

.method-btn.active {
  background: var(--bg-secondary-glass);
  color: var(--text-primary);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Info Panel (Right) */
.info-panel {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.metrics-card {
  background: var(--bg-elevated-glass);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  padding: 1.5rem;
  border-radius: 0.5rem;
  border: var(--glass-border);
}

.metric-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

.metric-val {
  font-weight: 700;
  font-family: monospace;
}

.metric-val.improving {
  color: var(--success);
}

.metric-val.baseline {
  color: var(--text-secondary);
}

.description-card {
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--text-secondary);
}

/* Comparison Grid */
.grid-gallery {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
  margin-top: 2rem;
}

.grid-gallery>div {
  /* Prevent grid items from blowing out the viewport due to table sizes (min-width: auto bug) */
  min-width: 0;
}

.grid-gallery img {
  width: 100%;
  border-radius: 0.5rem;
  border: var(--glass-border);
}

/* Table */
.results-table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.95rem;
}

.results-table th,
.results-table td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: var(--glass-border);
}

.results-table th {
  color: var(--text-primary);
  font-weight: 600;
}

/* Footer */
footer {
  padding: 2rem 0;
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

footer a {
  color: var(--accent-primary);
  text-decoration: none;
}

/* Responsive Breakpoints */
@media (max-width: 1024px) {
  .viewer-container {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto;
  }

  .sample-list {
    flex-direction: row;
    overflow-x: auto;
    max-height: none;
    padding-bottom: 0.5rem;
  }

  .sample-item {
    flex-direction: column;
    text-align: center;
    min-width: 80px;
  }

  .canvas-wrapper {
    width: 100%;
    max-width: 512px;
    height: auto;
    aspect-ratio: 1 / 1;
  }
}

@media (max-width: 768px) {
  .hero h1 {
    font-size: 2.2rem;
  }

  .science-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .method-tabs {
    flex-wrap: wrap;
    justify-content: center;
  }

  .metrics-card .metric-row {
    font-size: 1rem;
  }

  .container {
    padding: 0 1.5rem;
  }
}

@media (max-width: 480px) {
  .hero {
    padding: 3rem 1rem;
  }

  .hero .container {
    padding: 2rem 1.5rem;
    width: 100%;
    margin: 0 auto;
  }

  .cta-buttons {
    flex-direction: column;
    width: 100%;
    align-items: center;
  }

  .btn-primary,
  .btn-secondary {
    width: 100%;
    display: block;
    box-sizing: border-box;
  }

  .results-table {
    display: block;
    overflow-x: auto;
  }
}

/* --- Interactive 3D Viewer Custom UI (lil-gui) --- */
/* Custom lil-gui styling to match DeepLense theme */
.lil-gui.root {
  --background-color: var(--bg-elevated);
  --text-color: var(--text-primary);
  --title-background-color: var(--bg-secondary);
  --widget-color: rgba(6, 182, 212, 0.1);
  /* accent-primary dark */
  --hover-color: rgba(6, 182, 212, 0.3);
  --focus-color: var(--accent-primary);
  --number-color: var(--accent-primary);
  --string-color: var(--accent-secondary);
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
  border: 1px solid rgba(255, 255, 255, 0.05);
  overflow: hidden;
  /* Force position top right */
  position: fixed !important;
  top: 10px !important;
  right: 10px !important;
  bottom: auto !important;
  left: auto !important;
  transform: none !important;
}

.lil-gui .title {
  font-family: 'Inter', sans-serif;
  font-weight: 600;
  letter-spacing: 0.5px;
  padding-top: 1.5px;
  padding-bottom: 10px;
}