:root {
  --bg-page-light: #f1f5f9;
  --bg-page-dark: #090d16;
  --bg-panel-light: #ffffff;
  --bg-panel-dark: #111827;
  --bg-card-light: #f8fafc;
  --bg-card-dark: #1e293b;
  --text-main-light: #0f172a;
  --text-main-dark: #f8fafc;
  --text-muted-light: #475569;
  --text-muted-dark: #94a3b8;
  --border-light: #cbd5e1;
  --border-dark: #334155;
  --brand-accent-light: #0284c7;
  --brand-accent-dark: #38bdf8;

  --bg-page: var(--bg-page-dark);
  --bg-panel: var(--bg-panel-dark);
  --bg-card: var(--bg-card-dark);
  --text-main: var(--text-main-dark);
  --text-muted: var(--text-muted-dark);
  --border-color: var(--border-dark);
  --accent-color: var(--brand-accent-light);

  /* MANDATORY: Fallback for browsers without light-dark support */
  @media (prefers-color-scheme: dark) {
    --accent-color: var(--brand-accent-dark);
  }

  @supports (color: light-dark(white, black)) {
    --accent-color: light-dark(var(--brand-accent-light), var(--brand-accent-dark));
  }

  /* MANDATORY: Automatically adapt native UI to user system preferences */
  color-scheme: light dark;
  accent-color: var(--accent-color);
}

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

[hidden] {
  display: none !important;
}

html,
body {
  inline-size: 100%;
  block-size: 100dvh;
  background-color: var(--bg-page);
  color: var(--text-main);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-size: 13.5px;
  line-height: 1.45;
  overflow: clip;
}

.lab-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 420px;
  inline-size: 100%;
  block-size: 100dvh;
}

@media (max-width: 960px) {
  .lab-layout {
    grid-template-columns: 1fr;
    grid-template-rows: 55dvh 45dvh;
  }
}

.viewport-pane {
  position: relative;
  inline-size: 100%;
  block-size: 100%;
  background: #090d16;
  overflow: clip;
}

/* Remove inline baseline gap on replaced <canvas> elements by setting display: block */
canvas {
  display: block;
  inline-size: 100%;
  block-size: 100%;
}

#arenaCanvas {
  touch-action: none;
  -webkit-user-select: none;
  user-select: none;
}

#arenaCanvas.grab-hover {
  cursor: grab;
}

#arenaCanvas.dragging {
  cursor: grabbing;
}

.hud-overlay {
  position: absolute;
  inset-block-start: 14px;
  inset-inline-start: 14px;
  inset-inline-end: 14px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-start;
  gap: 10px;
  pointer-events: none;
}

.hud-badge-group {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  pointer-events: auto;
}

.hud-pill {
  background: rgba(15, 23, 42, 0.84);
  border: 1px solid rgba(56, 189, 248, 0.32);
  padding-block: 6px;
  padding-inline: 11px;
  border-radius: 8px;
  font-size: 12px;
  color: #e2e8f0;
  backdrop-filter: blur(8px);
}

.hud-pill strong {
  color: #38bdf8;
  font-variant-numeric: tabular-nums;
}

.hud-pill.gold strong {
  color: #fbbf24;
}

.hud-pill.emerald strong {
  color: #34d399;
}

.hud-bottom-bar {
  position: absolute;
  inset-block-end: 14px;
  inset-inline-start: 14px;
  inset-inline-end: 14px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  pointer-events: none;
}

.hud-legend {
  background: rgba(15, 23, 42, 0.82);
  border: 1px solid rgba(148, 163, 184, 0.22);
  border-radius: 8px;
  padding-block: 6px;
  padding-inline: 12px;
  font-size: 11.5px;
  color: #cbd5e1;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  pointer-events: auto;
}

.legend-dot {
  display: inline-block;
  inline-size: 9px;
  block-size: 9px;
  border-radius: 50%;
  margin-inline-end: 4px;
}

/* YouTube-style Center Pause / Play Overlay */
.yt-overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  pointer-events: none;
  z-index: 20;
}

.yt-circle-btn {
  inline-size: 88px;
  block-size: 88px;
  border-radius: 50%;
  background: rgba(15, 23, 42, 0.62);
  border: 2px solid rgba(248, 250, 252, 0.28);
  color: rgba(248, 250, 252, 0.95);
  display: grid;
  place-items: center;
  backdrop-filter: blur(5px);
  box-shadow: 0 10px 36px rgba(0, 0, 0, 0.55);
  pointer-events: auto;
  cursor: pointer;
  transition: transform 0.18s ease, background-color 0.18s ease, border-color 0.18s ease, opacity 0.25s ease;
  animation: ytPopIn 0.22s cubic-bezier(0.2, 0.85, 0.35, 1.15);
}

.yt-circle-btn:hover {
  background: rgba(15, 23, 42, 0.78);
  border-color: rgba(56, 189, 248, 0.65);
  transform: scale(1.06);
}

.yt-circle-btn:active {
  transform: scale(0.96);
}

.yt-circle-btn.resuming {
  pointer-events: none;
  border-color: rgba(52, 211, 153, 0.75);
  animation: ytResumePulse 1s ease forwards;
}

.yt-icon {
  display: block;
}

.yt-overlay[data-icon="pause"] .icon-play {
  display: none !important;
}

.yt-overlay[data-icon="play"] .icon-pause {
  display: none !important;
}

.yt-icon.play-shift {
  transform: translateX(2.5px);
}

@keyframes ytPopIn {
  0% {
    opacity: 0;
    transform: scale(0.72);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes ytResumePulse {
  0% {
    opacity: 1;
    transform: scale(1);
  }
  70% {
    opacity: 0.92;
    transform: scale(1.08);
  }
  100% {
    opacity: 0;
    transform: scale(1.22);
  }
}

.sidebar-pane {
  background-color: var(--bg-panel);
  border-inline-start: 1px solid var(--border-color);
  padding-block: 14px;
  padding-inline: 14px;
  overflow-y: auto;
  scrollbar-gutter: stable;
  overscroll-behavior: contain;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.lab-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  padding-block-end: 8px;
  border-block-end: 1px solid var(--border-color);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}

.lang-select {
  background-color: #0f172a;
  color: #f8fafc;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding-block: 3px;
  padding-inline: 6px;
  font-size: 11.5px;
  font-weight: 600;
  cursor: pointer;
}

.lang-select:focus-visible {
  outline: 2px solid var(--accent-color);
  outline-offset: 1px;
}

.lab-header h1 {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: #f8fafc;
}

.lab-subtitle {
  font-size: 11.5px;
  color: var(--text-muted);
}

.card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding-block: 10px;
  padding-inline: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.card-title {
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #38bdf8;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.control-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}

.control-field {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.control-field.full {
  grid-column: 1 / -1;
}

.control-field label {
  font-size: 11.5px;
  color: var(--text-muted);
  display: flex;
  justify-content: space-between;
}

select,
button,
input[type="range"] {
  font: inherit;
}

select {
  background: #0f172a;
  color: #f8fafc;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding-block: 6px;
  padding-inline: 8px;
  font-size: 12.5px;
}

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.btn {
  flex: 1 1 auto;
  background: #1e293b;
  color: #f8fafc;
  border: 1px solid #475569;
  border-radius: 6px;
  padding-block: 6px;
  padding-inline: 10px;
  font-size: 12px;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s;
}

.btn:hover {
  background: #334155;
}

.btn.primary {
  background: #0284c7;
  border-color: #38bdf8;
  color: #ffffff;
}

.btn.primary:hover {
  background: #0369a1;
}

.btn.emerald {
  background: #059669;
  border-color: #34d399;
  color: #ffffff;
}

.btn.emerald:hover {
  background: #047857;
}

.btn.amber-alert {
  background: #d97706;
  border-color: #fbbf24;
  color: #ffffff;
}

.btn:disabled {
  opacity: 0.6;
  cursor: wait;
}

.btn.active {
  background: #0ea5e9;
  border-color: #7dd3fc;
  color: #0f172a;
}

.speed-row {
  display: flex;
  gap: 5px;
}

.canvas-box {
  inline-size: 100%;
  block-size: 195px;
  background: #090d16;
  border: 1px solid #1e293b;
  border-radius: 8px;
  overflow: clip;
}

.canvas-box.chart {
  block-size: 155px;
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
}

.metric-item {
  background: #0f172a;
  border: 1px solid #1e293b;
  border-radius: 6px;
  padding-block: 6px;
  padding-inline: 8px;
}

.metric-label {
  font-size: 10.5px;
  color: var(--text-muted);
}

.metric-val {
  font-size: 14px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: #f8fafc;
}

.morph-desc {
  font-size: 11.5px;
  color: #cbd5e1;
  background: rgba(15, 23, 42, 0.6);
  padding-block: 6px;
  padding-inline: 8px;
  border-radius: 6px;
  border-inline-start: 3px solid #38bdf8;
}

.logs-list {
  max-block-size: 120px;
  overflow-y: auto;
  scrollbar-gutter: stable;
  overscroll-behavior: contain;
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-size: 11px;
}

.log-entry {
  display: flex;
  justify-content: space-between;
  background: #0f172a;
  padding-block: 4px;
  padding-inline: 8px;
  border-radius: 4px;
  color: #cbd5e1;
  font-variant-numeric: tabular-nums;
}

.checkbox-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  font-size: 12px;
  color: #cbd5e1;
}

.checkbox-row label {
  display: flex;
  align-items: center;
  gap: 5px;
  cursor: pointer;
}

.meta-badge {
  font-size: 10.5px;
  font-weight: 700;
  padding-block: 2px;
  padding-inline: 7px;
  border-radius: 999px;
  letter-spacing: 0.03em;
  white-space: nowrap;
  flex-shrink: 0;
}

.meta-badge.learning {
  background: rgba(16, 185, 129, 0.2);
  color: #34d399;
  border: 1px solid rgba(52, 211, 153, 0.45);
}

.meta-badge.consolidated {
  background: rgba(14, 165, 233, 0.2);
  color: #38bdf8;
  border: 1px solid rgba(56, 189, 248, 0.45);
}

.meta-badge.righting {
  background: rgba(245, 158, 11, 0.24);
  color: #fbbf24;
  border: 1px solid rgba(251, 191, 36, 0.55);
}

.meta-mode-banner {
  font-size: 12px;
  font-weight: 700;
  block-size: 34px;
  display: flex;
  align-items: center;
  padding-inline: 10px;
  border-radius: 7px;
  letter-spacing: 0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.meta-mode-banner.learning {
  background: rgba(6, 78, 59, 0.55);
  border: 1px solid #10b981;
  color: #a7f3d0;
}

.meta-mode-banner.consolidated {
  background: rgba(12, 74, 110, 0.55);
  border: 1px solid #38bdf8;
  color: #bae6fd;
}

.meta-mode-banner.righting {
  background: rgba(120, 53, 15, 0.65);
  border: 1px solid #f59e0b;
  color: #fde68a;
}

.meta-bars-grid {
  display: flex;
  flex-direction: column;
  gap: 7px;
}

.meta-bar-item {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.meta-bar-header {
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  color: #cbd5e1;
  font-variant-numeric: tabular-nums;
}

.meta-bar-header strong {
  color: #f8fafc;
}

.meta-bar-track {
  inline-size: 100%;
  block-size: 7px;
  background: #0f172a;
  border: 1px solid #334155;
  border-radius: 999px;
  overflow: clip;
}

.meta-bar-fill {
  block-size: 100%;
  background: linear-gradient(90deg, #0ea5e9, #34d399);
  border-radius: 999px;
  transition: inline-size 0.2s ease;
}

.meta-bar-fill.beetle {
  background: linear-gradient(90deg, #f59e0b, #fbbf24);
}

.meta-reason-box {
  font-size: 11.5px;
  color: #e2e8f0;
  background: rgba(15, 23, 42, 0.72);
  border-inline-start: 3px solid #34d399;
  block-size: 58px;
  padding-block: 6px;
  padding-inline: 8px;
  border-radius: 5px;
  line-height: 1.35;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
}

#ambitionButtons .btn {
  padding-inline: 6px;
  font-size: 11px;
}

/* HUD Robot Switcher Pill Button */
.hud-btn-morph {
  cursor: pointer;
  font-weight: 600;
  color: #f8fafc;
  border-color: rgba(56, 189, 248, 0.52);
  background: rgba(15, 23, 42, 0.88);
  transition: background-color 0.16s ease, border-color 0.16s ease, transform 0.14s ease;
}

.hud-btn-morph:hover {
  background: rgba(14, 165, 233, 0.25);
  border-color: #38bdf8;
  transform: translateY(-1px);
}

/* Native <dialog> for First-Visit Robot Body Morphology Selection over the 3D Viewport */
dialog:modal {
  overscroll-behavior: contain;
}

dialog::backdrop {
  overflow: hidden;
  overscroll-behavior: contain;
  background: rgba(9, 13, 22, 0.56);
  backdrop-filter: blur(5px);
}

.morph-picker-dialog {
  inset: 0;
  margin: auto;
  inline-size: min(760px, calc(100vw - 28px));
  max-block-size: calc(100dvh - 36px);
  background: rgba(15, 23, 42, 0.94);
  color: #f8fafc;
  border: 1px solid rgba(56, 189, 248, 0.42);
  border-radius: 16px;
  padding-block: 18px;
  padding-inline: 20px;
  box-shadow: 0 24px 64px rgba(0, 0, 0, 0.72), 0 0 0 1px rgba(255, 255, 255, 0.06);
  overflow-y: auto;
}

@media (min-width: 961px) {
  /* Center the modal dialog directly over the left 3D visualization viewport pane */
  .morph-picker-dialog {
    inset-inline-start: 0;
    inset-inline-end: 420px;
    inline-size: min(740px, calc(100vw - 456px));
  }
}

.morph-picker-dialog[open] {
  display: flex;
  flex-direction: column;
  gap: 16px;
  animation: ytPopIn 0.22s cubic-bezier(0.2, 0.85, 0.35, 1.12);
}

.morph-picker-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 12px;
}

.morph-picker-header h2 {
  font-size: 18px;
  font-weight: 700;
  color: #f8fafc;
  letter-spacing: -0.01em;
}

.morph-picker-subtitle {
  font-size: 12.5px;
  color: #94a3b8;
  margin-block-start: 3px;
}

.morph-dialog-close {
  background: rgba(30, 41, 59, 0.85);
  color: #cbd5e1;
  border: 1px solid #475569;
  border-radius: 8px;
  inline-size: 32px;
  block-size: 32px;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  flex-shrink: 0;
  display: grid;
  place-items: center;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.morph-dialog-close:hover {
  background: #334155;
  color: #ffffff;
  border-color: #94a3b8;
}

.morph-cards-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

@media (max-width: 720px) {
  .morph-cards-grid {
    grid-template-columns: 1fr;
  }
}

.morph-card {
  background: rgba(30, 41, 59, 0.82);
  border: 1.5px solid rgba(148, 163, 184, 0.28);
  border-radius: 12px;
  padding: 12px;
  text-align: start;
  color: #f8fafc;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 10px;
  transition: transform 0.16s ease, border-color 0.16s ease, background-color 0.16s ease, box-shadow 0.16s ease;
}

.morph-card:hover,
.morph-card:focus-visible {
  transform: translateY(-3px);
  border-color: #38bdf8;
  background: rgba(30, 41, 59, 0.98);
  box-shadow: 0 12px 28px rgba(2, 132, 199, 0.24);
  outline: none;
}

.morph-card.selected {
  border-color: #facc15;
  box-shadow: 0 0 0 1px rgba(250, 204, 21, 0.45), 0 10px 26px rgba(234, 179, 8, 0.18);
}

.morph-card-preview {
  position: relative;
  background: #090d16;
  border: 1px solid rgba(51, 65, 85, 0.75);
  border-radius: 9px;
  block-size: 118px;
  display: grid;
  place-items: center;
  overflow: clip;
}

.morph-svg {
  inline-size: 100%;
  block-size: 100%;
}

.morph-dof-badge {
  position: absolute;
  inset-block-start: 7px;
  inset-inline-end: 7px;
  font-size: 10px;
  font-weight: 700;
  padding-block: 2px;
  padding-inline: 7px;
  border-radius: 999px;
  background: rgba(14, 165, 233, 0.22);
  color: #38bdf8;
  border: 1px solid rgba(56, 189, 248, 0.45);
}

.morph-dof-badge.emerald {
  background: rgba(16, 185, 129, 0.22);
  color: #34d399;
  border-color: rgba(52, 211, 153, 0.45);
}

.morph-dof-badge.gold {
  background: rgba(245, 158, 11, 0.24);
  color: #fde047;
  border-color: rgba(250, 204, 21, 0.55);
}

.morph-card-body {
  display: flex;
  flex-direction: column;
  gap: 6px;
  flex: 1 1 auto;
}

.morph-card-title {
  font-size: 14px;
  font-weight: 700;
  color: #f8fafc;
}

.morph-card-desc {
  font-size: 11.5px;
  color: #cbd5e1;
  line-height: 1.38;
  flex: 1 1 auto;
}

.morph-card-cta {
  font-size: 11.5px;
  font-weight: 700;
  color: #38bdf8;
  margin-block-start: 4px;
}

.morph-card:hover .morph-card-cta,
.morph-card:focus-visible .morph-card-cta {
  color: #fde047;
}

.update-confirm-dialog {
  inline-size: min(500px, calc(100vw - 28px));
  border-color: rgba(250, 204, 21, 0.55);
}

@media (min-width: 961px) {
  .update-confirm-dialog {
    inset-inline-start: 0;
    inset-inline-end: 420px;
    inline-size: min(500px, calc(100vw - 456px));
  }
}

.update-dialog-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  flex-wrap: wrap;
  margin-block-start: 4px;
}

.update-dialog-actions .btn {
  padding-block: 9px;
  padding-inline: 14px;
  font-size: 13px;
}