:root {
  color-scheme: light dark;

  /* Base Light Tokens (Fallback for browsers without light-dark()) */
  --bg-canvas: #eef3fa;
  --panel-bg: rgba(255, 255, 255, 0.86);
  --panel-bg-solid: #ffffff;
  --panel-section-bg: rgba(15, 23, 42, 0.035);
  --panel-border: rgba(15, 23, 42, 0.12);
  --panel-highlight: rgba(255, 255, 255, 0.85);
  --surface-control: rgba(15, 23, 42, 0.055);
  --surface-control-hover: rgba(15, 23, 42, 0.11);
  --surface-well: rgba(15, 23, 42, 0.06);
  --text-main: #0f172a;
  --text-muted: #475569;
  --text-strong: #020617;
  --accent: #0284c7;
  --accent-soft: rgba(2, 132, 199, 0.14);
  --accent-border: rgba(2, 132, 199, 0.48);
  --accent-2: #7c3aed;
  --danger: #e11d48;
  --danger-soft: rgba(225, 29, 72, 0.14);
  --shadow-hud: 0 14px 36px rgba(15, 23, 42, 0.13);
  --scrollbar-thumb: rgba(71, 85, 105, 0.48);
  --scrollbar-track: rgba(15, 23, 42, 0.08);
  --kbd-bg: rgba(15, 23, 42, 0.08);
  --kbd-border: rgba(15, 23, 42, 0.18);
  --focus-ring: #0284c7;
  --fps-color: #16a34a;

  @media (prefers-color-scheme: dark) {
    --bg-canvas: #060911;
    --panel-bg: rgba(12, 17, 29, 0.86);
    --panel-bg-solid: #0f1626;
    --panel-section-bg: rgba(255, 255, 255, 0.028);
    --panel-border: rgba(255, 255, 255, 0.11);
    --panel-highlight: rgba(255, 255, 255, 0.06);
    --surface-control: rgba(255, 255, 255, 0.06);
    --surface-control-hover: rgba(255, 255, 255, 0.13);
    --surface-well: rgba(0, 0, 0, 0.34);
    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --text-strong: #ffffff;
    --accent: #38bdf8;
    --accent-soft: rgba(56, 189, 248, 0.17);
    --accent-border: rgba(56, 189, 248, 0.52);
    --accent-2: #a855f7;
    --danger: #f43f5e;
    --danger-soft: rgba(244, 63, 94, 0.18);
    --shadow-hud: 0 14px 36px rgba(0, 0, 0, 0.55);
    --scrollbar-thumb: rgba(148, 163, 184, 0.45);
    --scrollbar-track: rgba(15, 23, 42, 0.45);
    --kbd-bg: rgba(255, 255, 255, 0.1);
    --kbd-border: rgba(255, 255, 255, 0.2);
    --focus-ring: #7dd3fc;
    --fps-color: #4ade80;
  }

  /* Reflect <meta name="color-scheme"> override onto CSS color-scheme */
  &:has(> head > meta[name="color-scheme"][content="dark"]) {
    color-scheme: dark;
  }
  &:has(> head > meta[name="color-scheme"][content="light"]) {
    color-scheme: light;
  }

  @supports (color: light-dark(white, black)) {
    --bg-canvas: light-dark(#eef3fa, #060911);
    --panel-bg: light-dark(rgba(255, 255, 255, 0.87), rgba(12, 17, 29, 0.86));
    --panel-bg-solid: light-dark(#ffffff, #0f1626);
    --panel-section-bg: light-dark(rgba(15, 23, 42, 0.032), rgba(255, 255, 255, 0.028));
    --panel-border: light-dark(rgba(15, 23, 42, 0.12), rgba(255, 255, 255, 0.11));
    --panel-highlight: light-dark(rgba(255, 255, 255, 0.88), rgba(255, 255, 255, 0.06));
    --surface-control: light-dark(rgba(15, 23, 42, 0.055), rgba(255, 255, 255, 0.06));
    --surface-control-hover: light-dark(rgba(15, 23, 42, 0.11), rgba(255, 255, 255, 0.13));
    --surface-well: light-dark(rgba(15, 23, 42, 0.06), rgba(0, 0, 0, 0.34));
    --text-main: light-dark(#0f172a, #f1f5f9);
    --text-muted: light-dark(#475569, #94a3b8);
    --text-strong: light-dark(#020617, #ffffff);
    --accent: light-dark(#0284c7, #38bdf8);
    --accent-soft: light-dark(rgba(2, 132, 199, 0.14), rgba(56, 189, 248, 0.17));
    --accent-border: light-dark(rgba(2, 132, 199, 0.5), rgba(56, 189, 248, 0.52));
    --accent-2: light-dark(#7c3aed, #a855f7);
    --danger: light-dark(#e11d48, #f43f5e);
    --danger-soft: light-dark(rgba(225, 29, 72, 0.14), rgba(244, 63, 94, 0.18));
    --shadow-hud: light-dark(0 14px 34px rgba(15, 23, 42, 0.14), 0 14px 36px rgba(0, 0, 0, 0.55));
    --scrollbar-thumb: light-dark(rgba(71, 85, 105, 0.48), rgba(148, 163, 184, 0.45));
    --scrollbar-track: light-dark(rgba(15, 23, 42, 0.08), rgba(15, 23, 42, 0.45));
    --kbd-bg: light-dark(rgba(15, 23, 42, 0.08), rgba(255, 255, 255, 0.1));
    --kbd-border: light-dark(rgba(15, 23, 42, 0.2), rgba(255, 255, 255, 0.2));
    --focus-ring: light-dark(#0284c7, #7dd3fc);
    --fps-color: light-dark(#15803d, #4ade80);
  }

  --radius-lg: 14px;
  --radius-md: 9px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
  -webkit-user-select: none;
}

body,
html {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background-color: var(--bg-canvas);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Inter, sans-serif;
  color: var(--text-main);
  accent-color: var(--accent);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

:where(a, button, input, select, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
}

#simCanvas {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  cursor: crosshair;
  display: block;
  touch-action: none;
}

/* Floating Status Toast */
.hud-toast {
  position: fixed;
  top: 78px;
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  background: var(--panel-bg-solid);
  border: 1px solid var(--accent-border);
  color: var(--text-strong);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  pointer-events: none;
  opacity: 0;
  z-index: 30;
  box-shadow: var(--shadow-hud);
  transition: opacity 0.18s ease, transform 0.18s ease;
}

.hud-toast.visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Top HUD Bar */
.hud-top {
  position: fixed;
  top: 12px;
  left: 14px;
  right: 14px;
  height: 56px;
  background: var(--panel-bg);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 1px solid var(--panel-border);
  box-shadow: inset 0 1px 0 var(--panel-highlight), var(--shadow-hud);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 0 12px;
  z-index: 25;
}

.hud-left {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 9px;
}

.brand-mark {
  width: 14px;
  height: 14px;
  border-radius: 4px;
  transform: rotate(45deg);
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 14px color-mix(in srgb, var(--accent) 70%, transparent);
  flex-shrink: 0;
}

.brand-text {
  display: flex;
  align-items: center;
  gap: 8px;
}

.brand h1 {
  font-size: 0.92rem;
  font-weight: 900;
  letter-spacing: 0.13em;
  white-space: nowrap;
  color: var(--text-strong);
}

.status-pill {
  font-size: 0.62rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  padding: 2px 7px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  white-space: nowrap;
  border: 1px solid var(--panel-border);
  background: var(--surface-control);
  color: var(--text-muted);
}

.status-pill::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: currentColor;
}

.status-pill.live {
  color: var(--fps-color);
  border-color: color-mix(in srgb, var(--fps-color) 40%, transparent);
  background: color-mix(in srgb, var(--fps-color) 12%, transparent);
}

.status-pill.paused {
  color: #f59e0b;
  border-color: rgba(245, 158, 11, 0.42);
  background: rgba(245, 158, 11, 0.12);
}

.status-pill.slow {
  color: var(--accent);
  border-color: var(--accent-border);
  background: var(--accent-soft);
}

.status-pill.turbo {
  color: var(--accent-2);
  border-color: color-mix(in srgb, var(--accent-2) 50%, transparent);
  background: color-mix(in srgb, var(--accent-2) 16%, transparent);
}

@keyframes statusPulse {
  0%, 100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.55;
    transform: scale(1.25);
  }
}

.status-pill.live::before {
  box-shadow: 0 0 8px var(--fps-color);
  @media (prefers-reduced-motion: no-preference) {
    animation: statusPulse 2.2s ease-in-out infinite;
  }
}

/* Center Dropdown Menu Bar */
.hud-menus {
  display: flex;
  align-items: center;
  gap: 7px;
}

.mode-stepper {
  display: flex;
  align-items: center;
  gap: 3px;
  background: var(--surface-well);
  padding: 3px;
  border-radius: 11px;
  border: 1px solid var(--panel-border);
}

.menu-anchor-wrap {
  position: relative;
  display: inline-flex;
}

.menu-trigger {
  background: var(--surface-control);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  height: 36px;
  padding: 0 11px;
  border-radius: 9px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  white-space: nowrap;
  transition: background-color 0.15s ease, border-color 0.15s ease, scale 0.15s ease, box-shadow 0.15s ease;
}

.menu-trigger:hover {
  background: var(--surface-control-hover);
}

.menu-trigger:active {
  scale: 0.98;
}

.menu-trigger[aria-expanded="true"] {
  background: var(--accent-soft);
  border-color: var(--accent-border);
  box-shadow: 0 0 14px color-mix(in srgb, var(--accent) 22%, transparent);
}

.primary-trigger {
  min-width: 190px;
  justify-content: space-between;
  background: linear-gradient(135deg, var(--accent-soft), color-mix(in srgb, var(--accent-2) 14%, transparent));
  border-color: var(--accent-border);
}

.trigger-icon {
  font-size: 1rem;
  line-height: 1;
}

.trigger-copy {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  line-height: 1.1;
  text-align: left;
  margin-right: auto;
}

.trigger-copy small {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  font-weight: 800;
}

.trigger-copy strong {
  font-size: 0.82rem;
  color: var(--text-strong);
}

.chevron {
  font-size: 0.72rem;
  color: var(--text-muted);
  transition: transform 0.15s ease;
}

.menu-trigger[aria-expanded="true"] .chevron {
  transform: rotate(180deg);
  color: var(--accent);
}

/* Popover Dropdown Menus */
.hud-popover {
  background: var(--panel-bg-solid);
  color: var(--text-main);
  border: 1px solid var(--panel-border);
  border-radius: 13px;
  padding: 6px;
  min-width: 245px;
  max-width: min(360px, calc(100vw - 24px));
  max-height: min(76vh, 560px);
  overflow-y: auto;
  box-shadow: var(--shadow-hud), inset 0 1px 0 var(--panel-highlight);
}

.mode-popover {
  min-width: 300px;
}

.engine-popover {
  min-width: 270px;
}

.guide-popover {
  min-width: 340px;
  max-width: min(520px, calc(100vw - 24px));
  padding: 12px;
}

[popover].hud-popover:is(:popover-open, .\:popover-open) {
  display: block;
}

@supports (position-area: block-end) {
  [popover]:has(> [focusgroup~="menu"]),
  .hud-popover {
    position-area: block-end span-inline-end;
    position-try-fallbacks: flip-block, flip-inline, flip-block flip-inline;
    inset: auto;
    margin: 6px 0 0 0;
  }
}

@supports not (position-area: block-end) {
  .hud-popover {
    position: fixed;
    inset: auto;
    margin: 0;
  }
}

@media (prefers-reduced-motion: no-preference) {
  .hud-popover {
    opacity: 0;
    translate: 0 -0.25rem;
    transition: opacity, translate, display, overlay;
    transition-duration: 0.14s;
    transition-behavior: allow-discrete;
  }

  .hud-popover:is(:popover-open, .\:popover-open) {
    opacity: 1;
    translate: 0 0;
    transition-duration: 0.1s;
    @starting-style {
      opacity: 0;
      translate: 0 -0.25rem;
    }
  }
}

@media (prefers-reduced-motion: reduce) {
  .hud-popover {
    opacity: 0;
    transition: opacity, display, overlay;
    transition-duration: 0.1s;
    transition-behavior: allow-discrete;
  }

  .hud-popover:is(:popover-open, .\:popover-open) {
    opacity: 1;
    @starting-style {
      opacity: 0;
    }
  }
}

.menu-list {
  --menu-icon-size: 1.2rem;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.menu-section-label {
  font-size: 0.64rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  padding: 6px 10px 3px;
}

.menu-list hr {
  border: none;
  border-top: 1px solid var(--panel-border);
  margin: 4px 6px;
}

.menu-item {
  width: 100%;
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-main);
  padding: 7px 10px;
  border-radius: 8px;
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  text-align: left;
  transition: background-color 0.12s ease, border-color 0.12s ease;
}

.menu-item::before {
  content: "";
  flex: none;
  inline-size: var(--menu-icon-size);
  text-align: center;
  font-weight: 800;
  color: var(--accent);
}

.menu-item[aria-checked="true"]::before {
  content: "✓";
}

.menu-item[aria-checked="true"] {
  background: var(--accent-soft);
  border-color: var(--accent-border);
}

.menu-item:hover,
.menu-item:focus-visible {
  background: var(--surface-control-hover);
  outline: none;
}

.menu-item:focus-visible {
  border-color: var(--focus-ring);
}

.menu-icon {
  font-size: 1.05rem;
  width: 20px;
  text-align: center;
  flex-shrink: 0;
}

.menu-text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  min-width: 0;
}

.menu-text strong {
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-strong);
}

.menu-text small {
  font-size: 0.69rem;
  color: var(--text-muted);
  line-height: 1.25;
}

.menu-list .hint {
  margin-inline-start: auto;
  font-size: 0.68rem;
  color: var(--text-muted);
  background: var(--kbd-bg);
  border: 1px solid var(--kbd-border);
  border-radius: 5px;
  padding: 1px 6px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

/* Guide Popover */
.guide-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding-bottom: 8px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--panel-border);
}

.guide-header strong {
  font-size: 0.88rem;
  color: var(--text-strong);
}

.guide-header span {
  font-size: 0.72rem;
  color: var(--text-muted);
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(195px, 1fr));
  gap: 10px;
}

.guide-card {
  background: var(--panel-section-bg);
  border: 1px solid var(--panel-border);
  border-radius: 10px;
  padding: 9px 10px;
}

.guide-card h4 {
  font-size: 0.71rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 6px;
}

.guide-card ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 5px;
  font-size: 0.74rem;
  color: var(--text-main);
}

/* Top Controls */
.top-controls {
  display: flex;
  align-items: center;
  gap: 5px;
}

.icon-btn {
  background: var(--surface-control);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  height: 36px;
  padding: 0 10px;
  border-radius: 9px;
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  transition: background-color 0.15s ease, border-color 0.15s ease, scale 0.15s ease;
}

.compact-btn {
  width: 34px;
  padding: 0;
}

.speed-chip {
  min-width: 48px;
  font-variant-numeric: tabular-nums;
  font-weight: 800;
  color: var(--accent);
}

.icon-btn:hover {
  background: var(--surface-control-hover);
}

.icon-btn:active {
  scale: 0.96;
}

.icon-btn.active {
  border-color: var(--accent-border);
  background: var(--accent-soft);
  color: var(--accent);
}

.icon-btn.danger:hover {
  background: var(--danger-soft);
  border-color: var(--danger);
  color: var(--danger);
}

/* Two-State Theme Toggle Button Icon Branching (CSS-driven) */
.theme-toggle .theme-icon-moon,
.theme-toggle .theme-label-light {
  display: none;
}

@media (prefers-color-scheme: dark) {
  :root:not(:has(> head > meta[name="color-scheme"][content="light"])) .theme-toggle .theme-icon-sun,
  :root:not(:has(> head > meta[name="color-scheme"][content="light"])) .theme-toggle .theme-label-dark {
    display: none;
  }
  :root:not(:has(> head > meta[name="color-scheme"][content="light"])) .theme-toggle .theme-icon-moon,
  :root:not(:has(> head > meta[name="color-scheme"][content="light"])) .theme-toggle .theme-label-light {
    display: inline;
  }
}

:root:has(> head > meta[name="color-scheme"][content="dark"]) .theme-toggle .theme-icon-sun,
:root:has(> head > meta[name="color-scheme"][content="dark"]) .theme-toggle .theme-label-dark {
  display: none;
}

:root:has(> head > meta[name="color-scheme"][content="dark"]) .theme-toggle .theme-icon-moon,
:root:has(> head > meta[name="color-scheme"][content="dark"]) .theme-toggle .theme-label-light {
  display: inline;
}

/* Left Dock */
.hud-dock {
  position: fixed;
  top: 78px;
  left: 14px;
  bottom: 56px;
  width: 286px;
  background: var(--panel-bg);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius-lg);
  padding: 13px;
  z-index: 20;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track);
  box-shadow: inset 0 1px 0 var(--panel-highlight), var(--shadow-hud);
  transition: transform 0.22s ease, opacity 0.2s ease;
}

.hud-dock.collapsed {
  transform: translateX(calc(-100% - 24px));
  opacity: 0;
  pointer-events: none;
}

@supports not (scrollbar-color: auto) {
  .hud-dock::-webkit-scrollbar {
    width: 8px;
  }
  .hud-dock::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: 999px;
  }
  .hud-dock::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
  }
}

.dock-panel {
  display: none;
  flex-direction: column;
  gap: 14px;
}

.dock-panel.active {
  display: flex;
}

.panel-section {
  background: var(--panel-section-bg);
  border: 1px solid var(--panel-border);
  border-radius: 11px;
  padding: 11px;
}

.panel-section h3 {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.panel-section h3.sub-cat {
  margin-top: 11px;
  margin-bottom: 7px;
  padding-top: 9px;
  border-top: 1px solid var(--panel-border);
}

/* Active Element Info Card & Filter */
.element-info-card {
  display: flex;
  align-items: flex-start;
  gap: 9px;
  padding: 8px 9px;
  border-radius: 9px;
  background: var(--surface-well);
  border: 1px solid var(--panel-border);
  margin-bottom: 9px;
}

.info-swatch {
  width: 12px;
  height: 12px;
  margin-top: 3px;
  border-radius: 4px;
  background: var(--el-color);
  box-shadow: 0 0 10px var(--el-color);
  flex-shrink: 0;
}

.info-copy {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}

.info-copy strong {
  font-size: 0.81rem;
  color: var(--text-strong);
}

.info-copy small {
  font-size: 0.69rem;
  color: var(--text-muted);
  line-height: 1.3;
}

.search-wrap {
  margin-bottom: 10px;
}

.search-input {
  width: 100%;
  background: var(--surface-well);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  padding: 6px 10px;
  border-radius: 8px;
  font-size: 0.78rem;
  user-select: text;
  -webkit-user-select: text;
}

.search-input::placeholder {
  color: var(--text-muted);
}

/* Element Grid (Sand Mode) */
.element-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 5px;
}

.el-btn {
  background: var(--surface-control);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  padding: 7px 9px;
  border-radius: 8px;
  font-size: 0.76rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 7px;
  transition: background-color 0.14s ease, border-color 0.14s ease, box-shadow 0.14s ease, scale 0.12s ease;
}

.hidden-by-search,
.el-btn.hidden-by-search {
  display: none !important;
}

.el-btn:hover {
  background: var(--surface-control-hover);
}

.el-btn:active {
  scale: 0.97;
}

.el-btn.active {
  background: var(--accent-soft);
  border-color: var(--el-color);
  box-shadow: inset 0 0 0 1px var(--el-color);
  color: var(--text-strong);
}

.swatch {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--el-color);
  box-shadow: 0 0 8px var(--el-color);
  flex-shrink: 0;
}

/* Tool List */
.tool-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.tool-btn {
  background: var(--surface-control);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  padding: 8px 10px;
  border-radius: var(--radius-md);
  text-align: left;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 10px;
  transition: background-color 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease, scale 0.12s ease;
}

.tool-btn:hover {
  background: var(--surface-control-hover);
}

.tool-btn:active {
  scale: 0.985;
}

.tool-btn.active {
  background: linear-gradient(135deg, var(--accent-soft), color-mix(in srgb, var(--accent-2) 10%, transparent));
  border-color: var(--accent-border);
  box-shadow: 0 0 16px color-mix(in srgb, var(--accent) 18%, transparent), inset 0 1px 0 var(--panel-highlight);
}

.tool-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

.tool-btn div {
  display: flex;
  flex-direction: column;
}

.tool-btn strong {
  font-size: 0.81rem;
  color: var(--text-strong);
}

.tool-btn small {
  font-size: 0.69rem;
  color: var(--text-muted);
  margin-top: 2px;
}

/* Sliders, Selects & Toggles */
.slider-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.77rem;
  margin-bottom: 5px;
  color: var(--text-muted);
}

.slider-header span {
  color: var(--text-strong);
  font-weight: 700;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
  cursor: pointer;
}

.select-input {
  width: 100%;
  background: var(--surface-well);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  padding: 7px 10px;
  border-radius: 8px;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
}

@supports (appearance: base-select) {
  .select-input,
  .select-input::picker(select) {
    appearance: base-select;
  }

  .select-input::picker(select) {
    background: var(--panel-bg-solid);
    border: 1px solid var(--panel-border);
    border-radius: 10px;
    padding: 4px;
    color: var(--text-main);
    box-shadow: var(--shadow-hud);
  }

  .select-input option {
    padding: 6px 8px;
    border-radius: 6px;
    color: var(--text-main);
  }

  .select-input option:hover,
  .select-input option:checked {
    background: var(--accent-soft);
  }

  .select-input::picker-icon,
  .select-input option::checkmark {
    color: var(--accent);
  }
}

.toggle-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 11px;
  font-size: 0.78rem;
  color: var(--text-main);
  cursor: pointer;
}

.toggle-row input[type="checkbox"] {
  width: 15px;
  height: 15px;
  cursor: pointer;
}

/* Presets */
.preset-list {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.preset-btn {
  background: var(--surface-control);
  border: 1px solid var(--panel-border);
  color: var(--text-main);
  padding: 7px 10px;
  border-radius: 8px;
  font-size: 0.79rem;
  font-weight: 600;
  text-align: left;
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease, transform 0.15s ease;
}

.preset-btn:hover {
  background: var(--accent-soft);
  border-color: var(--accent-border);
  transform: translateX(2px);
}

/* Bottom Telemetry Bar */
.hud-bottom {
  position: fixed;
  bottom: 12px;
  left: 14px;
  right: 14px;
  height: 36px;
  background: var(--panel-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--panel-border);
  box-shadow: var(--shadow-hud);
  border-radius: 10px;
  padding: 0 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-size: 0.75rem;
  color: var(--text-muted);
  z-index: 20;
}

.telemetry {
  display: flex;
  align-items: center;
  gap: 7px;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

#fpsStat {
  color: var(--fps-color);
  font-weight: 800;
}

#timeScaleStat {
  color: var(--accent);
  font-weight: 800;
}

.inspector-pill {
  padding: 1px 7px;
  border-radius: 6px;
  background: var(--surface-well);
  border: 1px solid var(--panel-border);
  color: var(--text-strong);
  font-weight: 700;
}

.hint-text {
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  min-width: 0;
}

.shortcuts {
  display: flex;
  gap: 10px;
  white-space: nowrap;
}

kbd {
  background: var(--kbd-bg);
  border: 1px solid var(--kbd-border);
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 0.68rem;
  color: var(--text-strong);
}

@media (max-width: 1120px) {
  .btn-label,
  .shortcuts {
    display: none;
  }
  .primary-trigger {
    min-width: 155px;
  }
}

@media (max-width: 780px) {
  .brand-text,
  .home-btn-label {
    display: none;
  }
  .hud-dock {
    width: 235px;
  }
  .hint-text,
  .inspector-sep,
  .inspector-pill {
    display: none;
  }
}

/* ============================================================================
   HOME HUB & MACHINE FOUNDRY STYLES (CSS Grid + subgrid cards)
   ============================================================================ */

.home-hub-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 0 11px;
  height: 34px;
  border-radius: 10px;
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.2), rgba(168, 85, 247, 0.2));
  border: 1px solid var(--border-accent);
  color: var(--text-strong);
}

.home-hub-btn[aria-expanded="true"] {
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.38), rgba(168, 85, 247, 0.36));
  box-shadow: 0 0 16px rgba(56, 189, 248, 0.32);
}

.machine-chip {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 0 10px;
  height: 32px;
  font-size: 0.74rem;
  font-weight: 700;
  color: var(--accent-amber);
  border-color: rgba(245, 158, 11, 0.42);
  background: rgba(245, 158, 11, 0.12);
}

.machine-chip:hover {
  background: rgba(245, 158, 11, 0.22);
  border-color: var(--accent-amber);
}

.machine-preset-btn {
  border-color: rgba(56, 189, 248, 0.42);
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.14), rgba(168, 85, 247, 0.14));
  color: var(--text-strong);
  font-weight: 700;
}

.machine-preset-btn:hover {
  border-color: var(--accent-cyan);
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.26), rgba(168, 85, 247, 0.24));
}

.home-overlay {
  position: fixed;
  inset: 0;
  z-index: 60;
  width: 100%;
  height: 100dvh;
  overflow-y: auto;
  scrollbar-gutter: stable;
  overscroll-behavior: contain;
  background: light-dark(
    rgba(241, 245, 249, 0.84),
    rgba(5, 8, 18, 0.84)
  );
  backdrop-filter: blur(22px) saturate(165%);
  -webkit-backdrop-filter: blur(22px) saturate(165%);
  padding: 74px 24px 56px;
}

.home-overlay[hidden] {
  display: none;
}

.home-shell {
  max-width: 1260px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.home-hero {
  display: grid;
  grid-template-columns: 1.35fr 1fr;
  gap: 18px;
  padding: 24px;
  border-radius: 20px;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-glass);
  box-shadow: var(--shadow-lg), var(--inset-highlight);
}

.home-hero-copy {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.home-badge-row {
  display: flex;
  flex-wrap: wrap;
  flex-wrap: balance;
  gap: 8px;
}

.home-pill {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  background: var(--surface-subtle);
  border: 1px solid var(--border-glass);
  color: var(--text-muted);
}

.home-pill.accent {
  background: rgba(56, 189, 248, 0.16);
  border-color: var(--border-accent);
  color: var(--accent-cyan);
}

.home-title {
  margin: 0;
  font-size: clamp(1.55rem, 2.6vw, 2.25rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  color: var(--text-strong);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
}

.home-title-sub {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--accent-cyan);
  letter-spacing: 0.01em;
}

.home-lead {
  margin: 0;
  font-size: 0.88rem;
  line-height: 1.55;
  color: var(--text-main);
  max-width: 68ch;
}

.home-hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 4px;
}

.home-cta-btn {
  padding: 10px 16px;
  font-size: 0.82rem;
}

.machine-cta-btn {
  padding: 10px 16px;
  font-size: 0.82rem;
  border-color: rgba(245, 158, 11, 0.48);
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.2), rgba(244, 63, 94, 0.18));
  color: var(--text-strong);
}

.machine-cta-btn:hover {
  border-color: var(--accent-amber);
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.3), rgba(244, 63, 94, 0.28));
}

.home-telemetry-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 12px;
  padding: 16px;
  border-radius: 16px;
  background: var(--surface-subtle);
  border: 1px solid var(--border-glass);
}

.home-telemetry-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.7rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--text-muted);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-emerald);
  box-shadow: 0 0 10px var(--accent-emerald);
}

.home-stat-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px;
}

.home-stat-box {
  padding: 9px 11px;
  border-radius: 10px;
  background: var(--surface-card);
  border: 1px solid var(--border-glass);
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.home-stat-box small {
  font-size: 0.66rem;
  color: var(--text-muted);
}

.home-stat-box strong {
  font-size: 0.84rem;
  color: var(--text-strong);
}

.home-machine-strip {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.strip-label {
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
}

.strip-chips {
  display: flex;
  flex-wrap: wrap;
  flex-wrap: balance;
  gap: 6px;
}

.chip-btn {
  appearance: none;
  border: 1px solid var(--border-glass);
  background: var(--surface-card);
  color: var(--text-main);
  padding: 4px 9px;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.14s ease, border-color 0.14s ease, background-color 0.14s ease;
}

.chip-btn:hover {
  border-color: var(--accent-cyan);
  background: var(--surface-hover);
  color: var(--text-strong);
  transform: translateY(-1px);
}

/* Card Grid using CSS Grid + subgrid row alignment */
.home-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
  gap: 16px;
}

.lab-card {
  grid-row: span 4;
  display: grid;
  grid-template-rows: auto 1fr auto auto;
  grid-template-rows: subgrid;
  gap: 12px;
  padding: 18px;
  border-radius: 18px;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-glass);
  box-shadow: var(--shadow-lg), var(--inset-highlight);
  transition: transform 0.18s ease, border-color 0.18s ease;
}

.lab-card:hover {
  transform: translateY(-2px);
  border-color: var(--border-accent);
}

.lab-card.active-lab-card {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 1px var(--accent-cyan), var(--shadow-lg);
}

.lab-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 10px;
}

.lab-card-icon {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  font-size: 1.3rem;
  background: var(--surface-subtle);
  border: 1px solid var(--border-glass);
  flex-shrink: 0;
}

.lab-card-titles {
  flex: 1;
  min-width: 0;
}

.lab-card-kicker {
  display: block;
  font-size: 0.64rem;
  font-weight: 800;
  letter-spacing: 0.07em;
  color: var(--accent-cyan);
  text-transform: uppercase;
}

.lab-card-titles h3 {
  margin: 2px 0 0;
  font-size: 1rem;
  font-weight: 800;
  color: var(--text-strong);
}

.lab-card-badge {
  padding: 3px 8px;
  border-radius: 999px;
  font-size: 0.66rem;
  font-weight: 700;
  background: var(--surface-subtle);
  border: 1px solid var(--border-glass);
  color: var(--text-muted);
  white-space: nowrap;
}

.lab-card-desc {
  margin: 0;
  font-size: 0.8rem;
  line-height: 1.5;
  color: var(--text-main);
}

.tag-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  flex-wrap: balance;
  gap: 6px;
}

.tag-list li {
  font-size: 0.68rem;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--surface-subtle);
  border: 1px solid var(--border-glass);
  color: var(--text-muted);
}

.lab-card-footer {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  padding-top: 4px;
}

.machine-btn {
  border-color: rgba(245, 158, 11, 0.42);
  background: rgba(245, 158, 11, 0.12);
  color: var(--text-strong);
}

.machine-btn:hover {
  border-color: var(--accent-amber);
  background: rgba(245, 158, 11, 0.24);
}

.home-logo-emblem {
  display: inline-grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 11px;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.22), rgba(168, 85, 247, 0.22));
  border: 1px solid var(--border-accent);
  font-size: 1.35rem;
}

.box-cta-btn {
  padding: 10px 16px;
  font-size: 0.82rem;
  border-color: rgba(168, 85, 247, 0.55);
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.24), rgba(56, 189, 248, 0.2));
  color: var(--text-strong);
  font-weight: 700;
}

.box-cta-btn:hover {
  border-color: var(--accent-purple);
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.36), rgba(56, 189, 248, 0.3));
}

.highlight-chip {
  border-color: rgba(56, 189, 248, 0.48);
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.18), rgba(168, 85, 247, 0.18));
  color: var(--text-strong);
  font-weight: 700;
}

.home-graphic-showcase {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 12px;
  padding: 14px;
  border-radius: 16px;
  background: var(--surface-subtle);
  border: 1px solid var(--border-glass);
}

.home-graphic-stage {
  position: relative;
  width: 100%;
  height: 220px;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border-accent);
  background: light-dark(#e2e8f0, #050814);
  box-shadow: inset 0 0 28px rgba(56, 189, 248, 0.14);
}

#homeHeroCanvas {
  display: block;
  width: 100%;
  height: 100%;
  cursor: pointer;
}

.home-graphic-hud {
  position: absolute;
  inset: auto 10px 8px 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  pointer-events: none;
}

.graphic-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border-radius: 999px;
  font-size: 0.64rem;
  font-weight: 800;
  letter-spacing: 0.06em;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-glass);
  color: var(--text-strong);
}

.graphic-mini-btns {
  display: flex;
  gap: 6px;
  pointer-events: auto;
}

.mini-graphic-btn {
  appearance: none;
  padding: 3px 9px;
  border-radius: 8px;
  font-size: 0.68rem;
  font-weight: 700;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-accent);
  color: var(--text-strong);
  cursor: pointer;
}

.mini-graphic-btn:hover {
  background: var(--surface-hover);
  border-color: var(--accent-cyan);
}

.featured-box-card {
  border-color: rgba(56, 189, 248, 0.45);
  background: linear-gradient(160deg, rgba(56, 189, 248, 0.08), var(--bg-glass-strong) 48%);
}

/* Centerpiece Home Screen Hero & Animation Stage in the Middle */
.home-hero.home-hero-centered {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 16px;
}

.home-hero-top {
  display: flex;
  flex-direction: column;
  align-items: center;
  max-width: 860px;
}

.home-hero-top .home-badge-row {
  justify-content: center;
}

.home-hero-top .home-title {
  justify-content: center;
}

.home-centerpiece-stage {
  width: 100%;
  max-width: 980px;
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 12px;
  border-radius: 18px;
  background: var(--surface-subtle);
  border: 1px solid var(--border-accent);
  box-shadow: 0 12px 36px rgba(2, 6, 23, 0.28), inset 0 0 28px rgba(56, 189, 248, 0.1);
}

.centerpiece-canvas-wrap {
  height: 270px;
  border-radius: 14px;
}

.home-compendium-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 8px;
}

.compendium-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: 10px;
  background: var(--bg-glass-strong);
  border: 1px solid var(--border-glass);
  text-align: left;
}

.compendium-item strong {
  font-size: 1.25rem;
  font-weight: 900;
  color: var(--accent-cyan);
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.compendium-item span {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-main);
  line-height: 1.25;
}

.home-hero-bottom {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.home-hero-bottom .home-hero-actions {
  justify-content: center;
}

.home-hero-bottom .home-machine-strip {
  width: 100%;
  justify-content: center;
}

@media (prefers-reduced-motion: no-preference) {
  .home-logo-emblem {
    animation: emblemFloat 4.2s ease-in-out infinite;
  }
}

@keyframes emblemFloat {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-3px) rotate(8deg); }
}

@media (max-width: 960px) {
  .home-hero {
    grid-template-columns: 1fr;
  }
  .centerpiece-canvas-wrap {
    height: 220px;
  }
  .home-graphic-hud {
    flex-direction: column;
    align-items: stretch;
  }
  .graphic-mini-btns {
    flex-wrap: wrap;
    justify-content: center;
  }
}