:root,
[data-theme="dark"] {
  --bg-ground: #080c14;
  --bg-surface: #0f172a;
  --bg-surface-raised: #1e293b;
  --bg-surface-subtle: #162032;
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-medium: rgba(255, 255, 255, 0.15);
  --border-strong: rgba(255, 255, 255, 0.25);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent-ball: #d4f024;
  --accent-ball-text: #080c14;
  --accent-ball-glow: rgba(212, 240, 36, 0.22);
  --accent-clay: #e05a36;
  --accent-clay-bg: rgba(224, 90, 54, 0.12);
  --accent-grass: #2d6a4f;
  --accent-grass-bg: rgba(45, 106, 79, 0.15);
  --accent-hard: #3b82f6;
  --accent-hard-bg: rgba(59, 130, 246, 0.15);
  --accent-gold: #f59e0b;
  --court-line: rgba(255, 255, 255, 0.35);
  --court-surface: #0c1829;
  --court-inner: #132845;
  --shadow-card: 0 10px 32px -4px rgba(0, 0, 0, 0.45);
  --shadow-subtle: 0 4px 16px rgba(0, 0, 0, 0.25);
  --theme-toggle-bg: #1e293b;
  --theme-toggle-border: rgba(255, 255, 255, 0.15);
  --bg-header-glass: rgba(8, 12, 20, 0.85);
}

[data-theme="light"] {
  --bg-ground: #f8fafc;
  --bg-surface: #ffffff;
  --bg-surface-raised: #f1f5f9;
  --bg-surface-subtle: #e2e8f0;
  --border-subtle: rgba(0, 0, 0, 0.08);
  --border-medium: rgba(0, 0, 0, 0.14);
  --border-strong: rgba(0, 0, 0, 0.22);
  --text-primary: #090d16;
  --text-secondary: #334155;
  --text-muted: #475569;
  --accent-ball: #486000;
  --accent-ball-text: #ffffff;
  --accent-ball-glow: rgba(72, 96, 0, 0.15);
  --accent-clay: #9a2c0c;
  --accent-clay-bg: rgba(154, 44, 12, 0.08);
  --accent-grass: #1b4332;
  --accent-grass-bg: rgba(27, 67, 50, 0.08);
  --accent-hard: #0f3a7a;
  --accent-hard-bg: rgba(15, 58, 122, 0.08);
  --accent-gold: #b45309;
  --court-line: rgba(15, 58, 122, 0.4);
  --court-surface: #edf3fa;
  --court-inner: #dce7f5;
  --shadow-card: 0 8px 30px -4px rgba(15, 23, 42, 0.08);
  --shadow-subtle: 0 2px 10px rgba(15, 23, 42, 0.05);
  --theme-toggle-bg: #f1f5f9;
  --theme-toggle-border: rgba(0, 0, 0, 0.12);
  --bg-header-glass: rgba(248, 250, 252, 0.9);
}

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

html {
  font-family: 'Newsreader', 'Charter', 'Georgia', serif;
  background-color: var(--bg-ground);
  color: var(--text-primary);
  scroll-behavior: smooth;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body {
  line-height: 1.8;
  font-size: 1.15rem;
  background-color: var(--bg-ground);
  color: var(--text-primary);
  transition: background-color 0.25s ease, color 0.25s ease;
  min-height: 100vh;
}

/* Typography Hierarchy */
h1, h2, h3, h4, h5 {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  letter-spacing: -0.025em;
}

h1 {
  font-size: clamp(2.6rem, 6.5vw, 4.2rem);
  margin-bottom: 1.5rem;
  font-weight: 800;
  line-height: 1.15;
}

h2 {
  font-size: clamp(1.75rem, 3.8vw, 2.35rem);
  margin: 3.5rem 0 1.25rem;
  padding-bottom: 0.65rem;
  position: relative;
}

h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 48px;
  height: 3px;
  background-color: var(--accent-ball);
  border-radius: 2px;
}

h3 {
  font-size: 1.4rem;
  margin: 2rem 0 0.85rem;
  font-weight: 700;
}

h4 {
  font-size: 1.18rem;
  margin: 1.5rem 0 0.65rem;
}

p {
  margin-bottom: 1.65rem;
  color: var(--text-secondary);
}

strong {
  color: var(--text-primary);
  font-weight: 600;
}

em {
  font-style: italic;
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: opacity 0.2s ease;
}

a:hover {
  opacity: 0.8;
}

code, kbd, samp, pre {
  font-family: 'JetBrains Mono', 'SF Mono', Menlo, Consolas, monospace;
}

/* Layout containers */
.container {
  max-width: 840px;
  margin: 0 auto;
  padding: 0 1.75rem;
}

.container-wide {
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 1.75rem;
}

/* Skip Link Accessibility */
.skip-link {
  position: absolute;
  top: -999px;
  left: 1rem;
  background: var(--bg-surface-raised);
  color: var(--text-primary);
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-medium);
  border-radius: 8px;
  z-index: 1000;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
  box-shadow: var(--shadow-card);
  transition: top 0.15s ease;
}

.skip-link:focus {
  top: 1rem;
}

/* Header & Navigation — Understated & Compact Viewport Budget */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg-header-glass);
  border-bottom: 1px solid var(--border-subtle);
  border-top: 2px solid var(--accent-ball);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: background-color 0.25s ease, border-color 0.25s ease;
}

.header-content,
.nav-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 0.32rem;
  padding-bottom: 0.32rem;
  gap: 0.75rem;
}

.brand,
.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.42rem;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.86rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  white-space: nowrap;
  flex-shrink: 0;
}

.brand-link {
  color: var(--text-primary);
  text-decoration: none;
  font-weight: 600;
  transition: color 0.15s ease;
}

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

.brand-link:focus-visible {
  outline: 2px solid var(--accent-ball);
  outline-offset: 3px;
  border-radius: 4px;
}

.ball-pip {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--accent-ball);
  box-shadow: 0 0 5px var(--accent-ball);
  display: inline-block;
  flex-shrink: 0;
}

/* In-Page Section Jump Navigation */
.section-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-wrap: nowrap;
}

.section-link {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.74rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
  padding: 0.18rem 0.45rem;
  border-radius: 6px;
  white-space: nowrap;
  transition: color 0.15s ease, background-color 0.15s ease;
}

.section-link:hover {
  color: var(--text-primary);
  background-color: var(--bg-surface-subtle);
}

.section-link.active {
  color: var(--text-primary);
  font-weight: 600;
  background-color: var(--bg-surface-raised);
  box-shadow: inset 0 -1px 0 var(--accent-ball);
}

.section-link:focus-visible {
  outline: 2px solid var(--accent-ball);
  outline-offset: 2px;
}

@media (max-width: 820px) {
  .section-nav {
    display: none;
  }
}

/* In-page jump target scroll clearance for sticky header */
[id] {
  scroll-margin-top: 48px;
}

.header-controls,
.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  flex-shrink: 0;
}

/* Multilingual switcher */
.lang-nav,
.lang-selector-group {
  display: flex;
  align-items: center;
  background-color: var(--bg-surface-raised);
  border: 1px solid var(--theme-toggle-border);
  border-radius: 9999px;
  padding: 0.08rem;
  gap: 0.05rem;
}

.lang-link,
.lang-tab {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 0.14rem 0.42rem;
  border-radius: 9999px;
  text-decoration: none;
  color: var(--text-muted);
  transition: all 0.2s ease;
  line-height: 1.2;
}

.lang-link:hover,
.lang-tab:hover {
  color: var(--text-primary);
}

.lang-link.active,
.lang-tab.active {
  background-color: var(--accent-ball);
  color: var(--accent-ball-text);
}

/* Theme toggle */
.theme-toggle,
.theme-pill-btn {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.74rem;
  font-weight: 600;
  padding: 0.18rem 0.55rem;
  border-radius: 9999px;
  border: 1px solid var(--theme-toggle-border);
  background-color: var(--theme-toggle-bg);
  color: var(--text-primary);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: all 0.2s ease;
  white-space: nowrap;
  line-height: 1.2;
  min-height: 28px;
}

.theme-toggle:hover,
.theme-pill-btn:hover {
  background-color: var(--bg-surface-subtle);
  border-color: var(--border-medium);
}

/* Hero Section */
.hero-section {
  padding: clamp(3rem, 7vw, 5.5rem) 0 2rem;
  text-align: left;
}

.hero-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-bottom: 1.5rem;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.82rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.meta-tag {
  display: inline-block;
  padding: 0.25rem 0.7rem;
  border-radius: 6px;
  background-color: var(--bg-surface-raised);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

.meta-tag.highlight {
  background-color: var(--accent-ball-glow);
  color: var(--accent-ball);
  border-color: var(--accent-ball);
  font-weight: 700;
}

.hero-subtitle {
  font-size: 1.35rem;
  line-height: 1.65;
  color: var(--text-secondary);
  margin-bottom: 2.5rem;
  font-weight: 400;
}

/* Interactive Educational Tooltip (Desktop Hover & Mobile Tap) */
.tooltip-trigger {
  position: relative;
  display: inline;
  border-bottom: 1.5px dashed var(--accent-ball);
  cursor: help;
  color: inherit;
  font-weight: 500;
  text-decoration: none;
  transition: color 0.15s ease, border-bottom-color 0.15s ease;
}

.tooltip-trigger:hover,
.tooltip-trigger:focus-visible,
.tooltip-trigger.is-active {
  color: var(--text-primary);
  border-bottom-style: solid;
}

.tooltip-trigger:focus-visible {
  outline: 2px solid var(--accent-ball);
  outline-offset: 2px;
  border-radius: 2px;
}

.tooltip-box {
  position: absolute;
  bottom: calc(100% + 10px);
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  width: 320px;
  max-width: min(320px, 85vw);
  background-color: var(--bg-surface-raised);
  color: var(--text-secondary);
  border: 1px solid var(--border-medium);
  border-radius: 10px;
  padding: 0.85rem 1rem;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.82rem;
  line-height: 1.55;
  text-align: left;
  box-shadow: var(--shadow-card);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.2s cubic-bezier(0.16, 1, 0.3, 1), transform 0.2s cubic-bezier(0.16, 1, 0.3, 1), visibility 0.2s ease;
  z-index: 200;
  white-space: normal;
}

.tooltip-box strong {
  display: block;
  color: var(--text-primary);
  font-size: 0.88rem;
  margin-bottom: 0.35rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.tooltip-box::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border-width: 6px;
  border-style: solid;
  border-color: var(--border-medium) transparent transparent transparent;
}

.tooltip-trigger:hover .tooltip-box,
.tooltip-trigger:focus-visible .tooltip-box,
.tooltip-trigger.is-active .tooltip-box {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
  pointer-events: auto;
}

@media (max-width: 640px) {
  .tooltip-box {
    left: -20px;
    transform: translateY(4px);
    width: 280px;
    max-width: calc(100vw - 2.5rem);
  }

  .tooltip-box::after {
    left: 42px;
    transform: none;
  }

  .tooltip-trigger:hover .tooltip-box,
  .tooltip-trigger:focus-visible .tooltip-box,
  .tooltip-trigger.is-active .tooltip-box {
    transform: translateY(0);
  }
}

button:focus-visible,
a:focus-visible,
input:focus-visible {
  outline: 2px solid var(--accent-ball);
  outline-offset: 2px;
}

/* Key Metrics Ribbon */
.metrics-ribbon {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 1.25rem;
  margin: 2rem 0 3.5rem;
}

.metric-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.5rem 1.25rem;
  text-align: center;
  box-shadow: var(--shadow-card);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.metric-card:hover {
  transform: translateY(-3px);
  border-color: var(--border-medium);
}

.metric-value {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--text-primary);
  line-height: 1.1;
  margin-bottom: 0.35rem;
}

.metric-card.accent .metric-value {
  color: var(--accent-ball);
}

.metric-label {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.metric-sub {
  font-family: 'JetBrains Mono', 'SF Mono', monospace;
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-top: 0.35rem;
}

/* Tactile Editorial Dividers */
.court-net-divider {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin: 3.5rem 0;
}

.court-net-divider::before,
.court-net-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: repeating-linear-gradient(
    90deg,
    var(--border-subtle),
    var(--border-subtle) 6px,
    transparent 6px,
    transparent 12px
  );
}

.court-net-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.65rem;
  border-radius: 9999px;
  background-color: var(--bg-surface-raised);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* Interactive Simulator Section */
.simulator-container {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-medium);
  border-radius: 16px;
  padding: 1.25rem 1.5rem;
  margin: 2rem 0 3rem;
  box-shadow: var(--shadow-card);
}

.sim-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 0.85rem;
}

.sim-title-group h3 {
  margin: 0 0 0.2rem;
  font-size: 1.25rem;
  letter-spacing: -0.015em;
}

.sim-desc {
  font-size: 0.88rem;
  color: var(--text-secondary);
  margin-bottom: 0;
  max-width: 650px;
  line-height: 1.45;
}

.audio-toggle-btn {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.35rem 0.75rem;
  border-radius: 9999px;
  border: 1px solid var(--border-medium);
  background-color: var(--bg-surface-raised);
  color: var(--text-primary);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  transition: all 0.15s ease;
  white-space: nowrap;
}

.audio-toggle-btn.active {
  background-color: var(--accent-ball-glow);
  border-color: var(--accent-ball);
  color: var(--accent-ball);
}

/* Unified Control Toolbar */
.sim-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-bottom: 0.75rem;
}

.preset-button-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
}

.preset-btn {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.35rem 0.65rem;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background-color: var(--bg-surface-raised);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  white-space: nowrap;
}

.preset-btn:hover {
  border-color: var(--border-medium);
  color: var(--text-primary);
  background-color: var(--bg-surface-subtle);
}

.preset-btn.active {
  background-color: var(--accent-ball);
  color: var(--accent-ball-text);
  border-color: var(--accent-ball);
  font-weight: 700;
  box-shadow: 0 0 10px rgba(212, 240, 36, 0.25);
}

.preset-name {
  font-weight: 600;
}

.preset-badge {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.1rem 0.38rem;
  border-radius: 4px;
  background-color: var(--bg-surface-subtle);
  color: var(--text-muted);
  letter-spacing: -0.01em;
}

.preset-btn.active .preset-badge {
  background-color: rgba(0, 0, 0, 0.18);
  color: var(--accent-ball-text);
}

.preset-badge.badge-out {
  color: var(--accent-clay);
}
.preset-btn.active .preset-badge.badge-out {
  color: #7f1d1d;
  background-color: rgba(239, 68, 68, 0.25);
}

/* Surface Selector */
.surface-selector-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.surface-label {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-right: 0.15rem;
}

.surface-btn {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.32rem 0.65rem;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background-color: var(--bg-surface-raised);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  white-space: nowrap;
}

.surface-btn:hover {
  border-color: var(--border-medium);
  color: var(--text-primary);
}

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

.surface-sub {
  font-weight: 400;
  color: var(--text-muted);
  font-size: 0.74rem;
}

.surface-btn.active .surface-sub {
  color: var(--text-secondary);
}

.surface-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  display: inline-block;
}

.surface-dot.hard { background-color: var(--accent-hard); }
.surface-dot.clay { background-color: var(--accent-clay); }
.surface-dot.grass { background-color: var(--accent-grass); }

/* Dynamic Canvas — Viewport Budgeted for Laptops */
.canvas-wrapper {
  position: relative;
  width: 100%;
  height: clamp(240px, 30vh, 310px);
  background-color: var(--court-surface);
  border-radius: 12px 12px 0 0;
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  border-bottom: none;
}

#ball-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

/* Docked Instrument Telemetry Bar */
.telemetry-row {
  display: grid;
  grid-template-columns: 1.35fr 1fr 1fr 1fr;
  gap: 0.75rem;
  background-color: var(--bg-surface-raised);
  border-radius: 0 0 12px 12px;
  padding: 0.65rem 1rem;
  margin-top: 0;
  border: 1px solid var(--border-subtle);
  border-top: 1px solid var(--border-medium);
}

.telemetry-item {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.telemetry-lbl {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

.telemetry-val {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-top: 0.1rem;
  white-space: nowrap;
}

.badge-in {
  display: inline-block;
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
  background-color: var(--accent-grass-bg);
  color: var(--accent-grass);
  font-weight: 700;
  font-size: 0.76rem;
  margin-right: 0.25rem;
}

.badge-out {
  display: inline-block;
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
  background-color: var(--accent-clay-bg);
  color: var(--accent-clay);
  font-weight: 700;
  font-size: 0.76rem;
  margin-right: 0.25rem;
}

/* Slider Controls */
.sim-controls-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  padding: 0.85rem 0 0.25rem;
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.control-label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.control-val {
  font-family: 'JetBrains Mono', monospace;
  color: var(--text-primary);
  font-weight: 700;
  font-size: 0.82rem;
}

.range-slider {
  width: 100%;
  -webkit-appearance: none;
  appearance: none;
  height: 5px;
  border-radius: 3px;
  background: var(--bg-surface-subtle);
  outline: none;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent-ball);
  cursor: pointer;
  border: 2px solid var(--bg-surface);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.25);
}

.canvas-scale-caption {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.74rem;
  color: var(--text-muted);
  margin-top: 0.5rem;
  text-align: center;
  font-style: italic;
}

.range-slider::-moz-range-thumb {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent-ball);
  cursor: pointer;
  border: 2px solid var(--bg-surface);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.25);
}

/* Surface Comparison Matrix */
.surface-matrix-container {
  margin: 3.5rem 0 4rem;
}

.surface-matrix-intro {
  margin-bottom: 1.5rem;
}

.surface-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.surface-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.5rem;
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.surface-card:hover {
  transform: translateY(-3px);
  border-color: var(--border-medium);
}

.surface-card.hard-border { border-top: 4px solid var(--accent-hard); }
.surface-card.clay-border { border-top: 4px solid var(--accent-clay); }
.surface-card.grass-border { border-top: 4px solid var(--accent-grass); }

.surface-card h4 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.surface-card-subtitle {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.8rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
}

.surface-stat-list {
  list-style: none;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.86rem;
}

.surface-stat-row {
  display: flex;
  justify-content: space-between;
  padding: 0.45rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

.surface-stat-row:last-child {
  border-bottom: none;
}

.surface-stat-val {
  font-family: 'JetBrains Mono', monospace;
  font-weight: 700;
  color: var(--text-primary);
}

/* Tactical Court Radar & Heatmap */
.court-radar-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.75rem;
  margin: 2.5rem 0 3.5rem;
}

@media (max-width: 768px) {
  .court-radar-grid {
    grid-template-columns: 1fr;
  }
}

.tactical-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.75rem;
  box-shadow: var(--shadow-card);
}

.tactical-card h4 {
  font-size: 1.25rem;
  margin-bottom: 0.6rem;
}

.tactical-card p {
  font-size: 0.98rem;
  line-height: 1.65;
  margin-bottom: 1.25rem;
}

.tactical-stat-list {
  list-style: none;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.88rem;
}

.tactical-stat-item {
  display: flex;
  justify-content: space-between;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border-subtle);
}

.tactical-stat-item:last-child {
  border-bottom: none;
}

.tactical-stat-label {
  color: var(--text-secondary);
}

.tactical-stat-num {
  font-family: 'JetBrains Mono', monospace;
  font-weight: 700;
  color: var(--text-primary);
}

/* Video & Observation Guide */
.video-section {
  margin: 3.5rem 0 4rem;
}

.video-tabs-row {
  display: flex;
  gap: 0.65rem;
  margin-bottom: 1rem;
}

.video-tab-btn {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.85rem;
  font-weight: 600;
  padding: 0.45rem 1rem;
  border-radius: 8px;
  border: 1px solid var(--border-subtle);
  background-color: var(--bg-surface-raised);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
}

.video-tab-btn.active {
  background-color: var(--accent-ball);
  color: var(--accent-ball-text);
  border-color: var(--accent-ball);
  font-weight: 700;
}

.video-container {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  background-color: #000;
  margin-bottom: 0.85rem;
  box-shadow: var(--shadow-card);
}

.video-container iframe {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
}

.video-actions {
  display: flex;
  justify-content: flex-end;
  margin-bottom: 1.5rem;
}

.yt-direct-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 0.35rem 0.75rem;
  border-radius: 8px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  transition: color 0.15s ease, border-color 0.15s ease, background-color 0.15s ease;
}

.yt-direct-btn:hover {
  color: var(--text-primary);
  border-color: var(--border-medium);
  background-color: var(--bg-surface-raised);
}

.is-hidden {
  display: none !important;
}

.observation-guide {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.75rem;
  box-shadow: var(--shadow-card);
}

.guide-title {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 1.25rem;
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.guide-timeline {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.timeline-checkpoint {
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
}

.checkpoint-time {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.85rem;
  font-weight: 700;
  padding: 0.25rem 0.6rem;
  border-radius: 6px;
  background-color: var(--bg-surface-raised);
  border: 1px solid var(--border-subtle);
  color: var(--accent-ball);
  white-space: nowrap;
}

.checkpoint-content {
  flex: 1;
}

.checkpoint-heading {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.checkpoint-text {
  font-size: 0.94rem;
  line-height: 1.6;
  color: var(--text-secondary);
  margin-bottom: 0;
}

/* Milestone Interactive Matrix */
.milestones-wrapper {
  margin: 3rem 0 4rem;
}

.milestone-card {
  position: relative;
  padding: 1.75rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-card);
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.milestone-card:hover {
  border-color: var(--border-medium);
  transform: translateX(4px);
}

.milestone-header-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.65rem;
}

.milestone-year-tag {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.82rem;
  font-weight: 700;
  padding: 0.2rem 0.6rem;
  border-radius: 6px;
  background-color: var(--bg-surface-raised);
  border: 1px solid var(--border-subtle);
  color: var(--accent-ball);
  display: inline-block;
}

.milestone-surface-badge {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 0.2rem 0.55rem;
  border-radius: 4px;
}

.milestone-surface-badge.hard { background-color: var(--accent-hard-bg); color: var(--accent-hard); }
.milestone-surface-badge.grass { background-color: var(--accent-grass-bg); color: var(--accent-grass); }
.milestone-surface-badge.clay { background-color: var(--accent-clay-bg); color: var(--accent-clay); }

.milestone-card h4 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.milestone-card p {
  font-size: 1rem;
  line-height: 1.65;
  margin-bottom: 0.65rem;
}

.milestone-stat {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* Tactical Spotlight: Neutralizing Flat Pace */
.match-spotlight {
  background: linear-gradient(145deg, var(--bg-surface), var(--bg-surface-raised));
  border: 1px solid var(--border-medium);
  border-radius: 18px;
  padding: 2.25rem;
  margin: 3.5rem 0;
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
}

.spotlight-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.85rem;
  border-radius: 9999px;
  background-color: var(--accent-ball-glow);
  color: var(--accent-ball);
  border: 1px solid var(--accent-ball);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1.25rem;
}

.spotlight-title {
  font-size: 1.75rem;
  margin-bottom: 0.85rem;
}

.spotlight-summary {
  margin-bottom: 0;
  font-size: 0.96rem;
}

.duel-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.75rem;
  margin: 1.75rem 0;
}

@media (max-width: 680px) {
  .duel-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .metrics-ribbon {
    display: flex;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    gap: 0.75rem;
    padding-bottom: 0.5rem;
    margin: 1.25rem 0 2rem;
  }
  .metrics-ribbon::-webkit-scrollbar {
    height: 4px;
  }
  .metrics-ribbon::-webkit-scrollbar-thumb {
    background: var(--border-medium);
    border-radius: 4px;
  }
  .metric-card {
    flex: 0 0 160px;
    scroll-snap-align: start;
    padding: 0.85rem 0.65rem;
  }
  .metric-value {
    font-size: 1.45rem;
  }
  .metric-label {
    font-size: 0.75rem;
  }
  .metric-sub {
    font-size: 0.7rem;
  }
  .simulator-container {
    padding: 1rem 0.85rem;
    margin: 1.5rem 0 2.5rem;
  }
  .sim-toolbar {
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
  }
  .preset-button-row {
    display: flex;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    gap: 0.35rem;
    padding-bottom: 0.25rem;
  }
  .preset-btn {
    flex-shrink: 0;
    scroll-snap-align: start;
    font-size: 0.76rem;
    padding: 0.3rem 0.55rem;
  }
  .surface-selector-row {
    justify-content: flex-start;
  }
  .surface-btn {
    font-size: 0.74rem;
    padding: 0.25rem 0.55rem;
  }
  .canvas-wrapper {
    height: 220px;
  }
  .telemetry-row {
    grid-template-columns: 1fr 1fr;
    padding: 0.5rem 0.75rem;
    gap: 0.5rem;
  }
  .telemetry-lbl {
    font-size: 0.64rem;
  }
  .telemetry-val {
    font-size: 0.86rem;
  }
  .sim-controls-grid {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }
  .header-content {
    gap: 0.5rem;
    padding-top: 0.6rem;
    padding-bottom: 0.6rem;
  }
  .brand {
    font-size: 0.88rem;
  }
  .lang-link {
    padding: 0.2rem 0.45rem;
    font-size: 0.74rem;
  }
  .theme-toggle {
    padding: 0.35rem 0.65rem;
    font-size: 0.78rem;
    min-height: 32px;
  }
}


.player-box {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  padding: 1.5rem;
}

.player-box.alcaraz {
  border-left: 4px solid var(--accent-ball);
}

.player-box.wu {
  border-left: 4px solid var(--accent-hard);
}

.player-name {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.player-style {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.82rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.85rem;
}

.player-features {
  list-style: none;
  font-size: 0.92rem;
  line-height: 1.55;
  color: var(--text-secondary);
}

.player-features li {
  margin-bottom: 0.45rem;
  padding-left: 1.2rem;
  position: relative;
}

.player-features li::before {
  content: '•';
  position: absolute;
  left: 0;
  color: var(--text-muted);
}

/* Site Footer */
.site-footer {
  margin-top: 6rem;
  padding: 3.5rem 0 4.5rem;
  border-top: 1px solid var(--border-subtle);
  background-color: var(--bg-surface);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

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

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

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

.footer-notes {
  font-size: 0.84rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* Editorial quote block */
.quote-block {
  border-left: 3px solid var(--accent-ball);
  padding: 1.25rem 0 1.25rem 1.75rem;
  margin: 2.25rem 0;
  background-color: var(--bg-surface);
  border-radius: 0 10px 10px 0;
  box-shadow: var(--shadow-subtle);
}

.quote-text {
  font-style: italic;
  font-size: 1.25rem;
  line-height: 1.65;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.quote-author {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-muted);
}