/* ==========================================================================
   THEME DESIGN TOKENS & SYSTEM VARIABLES
   Derived from generative seed: hqhJMydlW8nB7bQnxNX0XCiWJaKUmFi1sCGIdXPZZb6RWqXEtpHd9r0Kc8UCcKCu
   Subpatterns: B7b (#b77b52 wood), c8UC (#f5f0e6 parchment), NX0X (#0e121a obsidian)
   ========================================================================== */

:root {
  /* LIGHT THEME (Default or data-theme="light") - High Contrast WCAG AAA */
  --bg-canvas: #f5f0e6;
  --bg-surface: #faf7f2;
  --bg-surface-elevated: #ffffff;
  --bg-surface-inset: #ebe4d5;
  --bg-surface-muted: #e4ddcd;

  --text-primary: #0a0e17;       /* 16.8:1 contrast on canvas */
  --text-secondary: #1e2633;     /* 12.4:1 contrast on canvas */
  --text-muted: #475364;         /* 5.2:1 contrast (WCAG AAA for large, AA for normal) */
  --text-accent: #8b3c1b;        /* Cordyceps ochre, deep ink contrast */

  --border-subtle: #d6ccb9;
  --border-strong: #8c7660;
  --border-focus: #0a0e17;

  --accent-wood: #9c5c2d;
  --accent-wood-hover: #804a22;
  --accent-moss: #2b4c34;
  --accent-rust: #8b3c1b;
  --accent-string: #6c4b2c;
  --accent-glow: rgba(156, 92, 45, 0.15);

  --shadow-sm: 0 1px 3px rgba(10, 14, 23, 0.08);
  --shadow-md: 0 4px 12px rgba(10, 14, 23, 0.1);
  --shadow-lg: 0 12px 28px rgba(10, 14, 23, 0.12);

  --font-serif: "Newsreader", "Charter", "Georgia", "Cambria", serif;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Menlo, Monaco, Consolas, monospace;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 14px;
  --radius-pill: 9999px;

  --content-max-width: 780px;
  --container-max-width: 1100px;
}

[data-theme="dark"] {
  /* DARK THEME - Deep Obsidian, Warm Resonant Wood & Overgrown Lichen */
  --bg-canvas: #0e121a;
  --bg-surface: #151b24;
  --bg-surface-elevated: #1d2532;
  --bg-surface-inset: #090c12;
  --bg-surface-muted: #242e3e;

  --text-primary: #f5f0e6;       /* 15.5:1 contrast on obsidian */
  --text-secondary: #d8d1c3;     /* 11.8:1 contrast */
  --text-muted: #9aa5b6;         /* 5.8:1 contrast */
  --text-accent: #e58d5c;

  --border-subtle: #293444;
  --border-strong: #b77b52;
  --border-focus: #f5f0e6;

  --accent-wood: #d49563;
  --accent-wood-hover: #e5aa7a;
  --accent-moss: #5a8a68;
  --accent-rust: #d96845;
  --accent-string: #d4a373;
  --accent-glow: rgba(212, 149, 99, 0.2);

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 14px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.6);
}

/* ==========================================================================
   BASE & RESET
   ========================================================================== */

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

html {
  font-size: 18px;
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  background-color: var(--bg-canvas);
  color: var(--text-primary);
  transition: background-color 0.25s ease, color 0.25s ease;
}

body {
  font-family: var(--font-serif);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-color: var(--bg-canvas);
  color: var(--text-primary);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

/* Focus styles for keyboard accessibility */
:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* Skip link */
.skip-link {
  position: absolute;
  top: -999px;
  left: 1rem;
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  z-index: 1000;
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
}
.skip-link:focus {
  top: 1rem;
}

/* ==========================================================================
   NAVIGATION & HEADER
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg-canvas);
  border-bottom: 1px solid var(--border-subtle);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

.header-inner {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0.75rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.brand-link:hover {
  color: var(--accent-wood);
}

.brand-mark {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--accent-wood);
  box-shadow: 0 0 8px var(--accent-glow);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

/* Language and Theme Pill Buttons */
.pill-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.75rem;
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s ease;
  user-select: none;
}

.pill-btn:hover {
  background-color: var(--bg-surface-elevated);
  border-color: var(--border-strong);
  color: var(--text-primary);
  transform: translateY(-1px);
}

.pill-btn:active {
  transform: translateY(0);
}

.pill-btn.active {
  background-color: var(--bg-surface-inset);
  border-color: var(--border-strong);
  color: var(--text-primary);
}

/* ==========================================================================
   LAYOUT CONTAINERS & TYPOGRAPHY
   ========================================================================== */

main {
  flex: 1;
}

.prose-container {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.wide-container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Hero Section */
.hero-section {
  padding: 3.5rem 0 2rem;
  border-bottom: 1px solid var(--border-subtle);
  position: relative;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent-wood);
  margin-bottom: 1rem;
}

.kicker::after {
  content: "";
  display: inline-block;
  width: 24px;
  height: 1px;
  background-color: var(--accent-wood);
}

.article-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 5vw, 3.1rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 1.25rem;
}

.article-deck {
  font-family: var(--font-serif);
  font-size: clamp(1.1rem, 2.5vw, 1.3rem);
  line-height: 1.5;
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  font-style: italic;
}

.meta-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.25rem;
  padding-top: 1rem;
  border-top: 1px dashed var(--border-subtle);
  font-family: var(--font-sans);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.meta-item {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.meta-badge {
  display: inline-block;
  padding: 0.15rem 0.45rem;
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface-inset);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
}

/* ==========================================================================
   ESSAY PROSE & EDITORIAL ELEMENTS
   ========================================================================== */

.editorial-body {
  padding: 2.5rem 0 4rem;
}

.editorial-body p {
  margin-bottom: 1.5rem;
  color: var(--text-secondary);
  font-size: 1.05rem;
  line-height: 1.75;
}

.editorial-body p.lead {
  font-size: 1.25rem;
  line-height: 1.65;
  color: var(--text-primary);
}

.editorial-body h2 {
  font-family: var(--font-serif);
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  margin: 3rem 0 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-subtle);
  letter-spacing: -0.015em;
}

.editorial-body h3 {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--text-primary);
  margin: 2rem 0 0.75rem;
}

.quote-panel {
  margin: 2rem 0;
  padding: 1.5rem 1.75rem;
  background-color: var(--bg-surface);
  border-left: 3px solid var(--accent-wood);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-style: italic;
}

.quote-panel p {
  font-size: 1.1rem;
  line-height: 1.6;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.quote-panel cite {
  display: block;
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-style: normal;
  color: var(--text-muted);
  font-weight: 500;
}

/* ==========================================================================
   INTERACTIVE WIDGET 1: ACOUSTIC RONROCO SIMULATOR
   ========================================================================== */

.interactive-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  margin: 2.5rem 0;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.widget-header {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.widget-title-group h3 {
  font-family: var(--font-sans);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0 0 0.25rem 0;
}

.widget-subtitle {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.audio-toggle-group {
  display: inline-flex;
  background-color: var(--bg-surface-inset);
  padding: 0.2rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-subtle);
}

.mode-btn {
  padding: 0.3rem 0.75rem;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  font-weight: 600;
  border: none;
  background: transparent;
  color: var(--text-muted);
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: all 0.2s ease;
}

.mode-btn.active {
  background-color: var(--bg-surface-elevated);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}

/* Fretboard / String Bed */
.fretboard {
  background: linear-gradient(180deg, var(--bg-surface-inset) 0%, var(--bg-surface) 100%);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.5rem 1rem;
  margin: 1.25rem 0;
  position: relative;
}

.string-course {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 0.75rem 0;
  padding: 0.5rem 0.75rem;
  background-color: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.15s ease;
  user-select: none;
}

.string-course:hover {
  border-color: var(--accent-wood);
  transform: translateX(4px);
  background-color: var(--bg-surface-muted);
}

.string-course:active, .string-course.plucked {
  background-color: var(--bg-surface-inset);
  border-color: var(--accent-wood);
  box-shadow: inset 0 0 10px var(--accent-glow);
}

.course-info {
  display: flex;
  flex-direction: column;
  min-width: 90px;
}

.course-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-wood);
}

.course-tuning {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.string-wire-container {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 4px;
  position: relative;
  height: 24px;
  justify-content: center;
}

.string-wire {
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--border-subtle) 0%, var(--accent-string) 50%, var(--border-subtle) 100%);
  border-radius: 1px;
  transition: transform 0.05s ease;
}

.string-course.plucked .string-wire {
  animation: stringVibrate 0.4s ease-out;
  background: linear-gradient(90deg, var(--accent-wood) 0%, var(--text-primary) 50%, var(--accent-wood) 100%);
}

@keyframes stringVibrate {
  0% { transform: scaleY(3) translateY(-2px); }
  25% { transform: scaleY(2) translateY(2px); }
  50% { transform: scaleY(1.5) translateY(-1px); }
  75% { transform: scaleY(1.2) translateY(1px); }
  100% { transform: scaleY(1) translateY(0); }
}

.course-key {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.2rem 0.5rem;
  background-color: var(--bg-surface-inset);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-muted);
}

.acoustic-readout {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-subtle);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.acoustic-readout span strong {
  color: var(--text-primary);
}

/* ==========================================================================
   INTERACTIVE WIDGET 2: 6/8 TIME SIGNATURE & ASYMMETRY
   ========================================================================== */

.meter-visualizer {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 0.5rem;
  margin: 1.5rem 0;
}

.beat-cell {
  background-color: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1rem 0.5rem;
  text-align: center;
  transition: all 0.2s ease;
}

.beat-cell.primary-pulse {
  border-color: var(--accent-wood);
  border-width: 2px;
  background-color: var(--bg-surface-inset);
}

.beat-cell.active-beat {
  background-color: var(--accent-wood);
  color: #ffffff;
  border-color: var(--accent-wood);
  transform: scale(1.05);
  box-shadow: 0 0 14px var(--accent-glow);
}

.beat-num {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  display: block;
}

.beat-role {
  font-family: var(--font-sans);
  font-size: 0.7rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-top: 0.25rem;
}

.beat-cell.active-beat .beat-role {
  color: #ffffff;
}

.meter-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.playback-controls {
  display: flex;
  gap: 0.5rem;
}

/* Negative Space Ratio Bar */
.ratio-bar-container {
  margin: 1.5rem 0 0.5rem;
}

.ratio-bar-label {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
  color: var(--text-secondary);
}

.ratio-track {
  height: 14px;
  background-color: var(--bg-surface-inset);
  border-radius: var(--radius-pill);
  overflow: hidden;
  display: flex;
  border: 1px solid var(--border-subtle);
}

.ratio-active {
  width: 51.7%;
  background: linear-gradient(90deg, var(--accent-wood) 0%, var(--accent-rust) 100%);
}

.ratio-space {
  width: 48.3%;
  background: repeating-linear-gradient(
    45deg,
    var(--bg-surface-muted),
    var(--bg-surface-muted) 6px,
    var(--bg-surface-inset) 6px,
    var(--bg-surface-inset) 12px
  );
}

/* ==========================================================================
   YOUTUBE EMBED & AUDITORY GUIDE
   ========================================================================== */

.video-section {
  margin: 3rem 0;
}

.video-wrapper {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%; /* 16:9 Aspect Ratio */
  height: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: var(--bg-surface-inset);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-md);
}

.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

.listening-guide {
  margin-top: 1.5rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
}

.guide-title {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--accent-wood);
  margin-bottom: 0.75rem;
}

.timestamp-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.timestamp-item {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.timestamp-badge {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.15rem 0.45rem;
  background-color: var(--bg-surface-inset);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--accent-wood);
  flex-shrink: 0;
}

/* ==========================================================================
   COMPARATIVE TABLE & MATRICES
   ========================================================================== */

.comparison-table-wrapper {
  margin: 2rem 0;
  overflow-x: auto;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  background-color: var(--bg-surface);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  text-align: left;
}

.comparison-table th, .comparison-table td {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-subtle);
}

.comparison-table th {
  background-color: var(--bg-surface-inset);
  font-weight: 700;
  color: var(--text-primary);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.comparison-table tr:last-child td {
  border-bottom: none;
}

.comparison-table td:first-child {
  font-weight: 600;
  color: var(--text-primary);
  width: 25%;
}

.comparison-table td.highlight-col {
  background-color: var(--bg-surface-muted);
  color: var(--text-primary);
}

/* ==========================================================================
   CANVAS SPECTRUM DISPLAY
   ========================================================================== */

.canvas-container {
  width: 100%;
  height: 220px;
  background-color: var(--bg-surface-inset);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  position: relative;
  margin: 1.25rem 0;
}

canvas.acoustic-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

/* ==========================================================================
   FOOTER (Strict Canonical Standards)
   - No personal GitHub profile link
   - Strictly bounded to mariuscomper.uk, language switch, machine readable links
   ========================================================================== */

.site-footer {
  margin-top: auto;
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  padding: 2.5rem 0;
  font-family: var(--font-sans);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-inner {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.footer-top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.footer-brand {
  font-weight: 600;
  color: var(--text-primary);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.25rem;
  list-style: none;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--text-primary);
  text-decoration: underline;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.78rem;
}

/* ==========================================================================
   RESPONSIVE QUERIES
   ========================================================================== */

@media (max-width: 640px) {
  html {
    font-size: 16px;
  }
  
  .hero-section {
    padding: 2.5rem 0 1.5rem;
  }
  
  .article-title {
    font-size: 1.85rem;
  }
  
  .meter-visualizer {
    grid-template-columns: repeat(3, 1fr);
  }
  
  .fretboard {
    padding: 1rem 0.5rem;
  }
  
  .string-course {
    gap: 0.5rem;
    padding: 0.4rem 0.5rem;
  }
  
  .course-info {
    min-width: 65px;
  }
  
  .header-inner {
    padding: 0.6rem 1rem;
  }
}