:root {
  color-scheme: dark;
  --bg: #070b0e;
  --panel: #0d1318;
  --panel-2: #111a20;
  --line: #26343d;
  --text: #e8f0f4;
  --muted: #91a3ad;
  --cyan: #49d6e9;
  --green: #57d68d;
  --coral: #ff6678;
  --amber: #f4c65d;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

* {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  min-height: 100%;
  margin: 0;
  overflow-x: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  letter-spacing: 0;
}

button,
input {
  font: inherit;
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

.lab-shell {
  display: grid;
  grid-template-rows: 54px auto minmax(0, 1fr) auto;
  min-height: 100vh;
}

.lab-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-width: 0;
  padding: 0 1rem;
  border-bottom: 1px solid var(--line);
  background: #090e12;
  color: var(--muted);
  font-size: 0.78rem;
}

.lab-header > div {
  display: flex;
  align-items: center;
  min-width: 0;
}

.brand {
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.9rem;
  font-weight: 800;
  text-decoration: none;
}

.header-separator {
  margin: 0 0.55rem;
  color: #53646e;
}

.runtime-state {
  white-space: nowrap;
}

.runtime-state i {
  width: 7px;
  height: 7px;
  margin-right: 0.45rem;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 12px rgba(87, 214, 141, 0.7);
}

.pattern-nav {
  display: grid;
  grid-template-columns: repeat(6, minmax(110px, 1fr));
  overflow-x: auto;
  border-bottom: 1px solid var(--line);
  background: var(--panel);
  scrollbar-width: thin;
}

.pattern-nav button {
  min-width: 0;
  padding: 0.85rem 0.9rem;
  border: 0;
  border-right: 1px solid var(--line);
  border-bottom: 2px solid transparent;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  text-align: left;
}

.pattern-nav button span,
.pattern-nav button strong {
  display: block;
}

.pattern-nav button span {
  margin-bottom: 0.3rem;
  color: #647780;
  font-family: var(--mono);
  font-size: 0.63rem;
}

.pattern-nav button strong {
  overflow: hidden;
  font-size: 0.76rem;
  font-weight: 650;
  line-height: 1.25;
  text-overflow: ellipsis;
}

.pattern-nav button:hover,
.pattern-nav button.is-active {
  background: #111a20;
  color: var(--text);
}

.pattern-nav button.is-active {
  border-bottom-color: var(--cyan);
}

.lab-main {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 330px;
  min-height: 0;
}

.stage {
  position: relative;
  min-width: 0;
  min-height: 580px;
  overflow: hidden;
  border-right: 1px solid var(--line);
  background: #05090c;
}

.scene,
.scene canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.stage-title {
  position: absolute;
  top: 1rem;
  left: 1rem;
  display: grid;
  grid-template-columns: 2.25rem minmax(0, 1fr);
  gap: 0.75rem;
  max-width: min(560px, calc(100% - 2rem));
  pointer-events: none;
}

.stage-title > span {
  padding-top: 0.2rem;
  color: var(--amber);
  font-family: var(--mono);
  font-size: 0.72rem;
}

.stage-title h1 {
  margin: 0;
  font-size: clamp(1.15rem, 2.1vw, 1.7rem);
  line-height: 1.1;
}

.stage-title p {
  margin: 0.45rem 0 0;
  color: var(--muted);
  font-size: 0.76rem;
  line-height: 1.45;
}

.stage-legend {
  position: absolute;
  bottom: 0.9rem;
  left: 1rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.62rem;
  pointer-events: none;
}

.stage-legend span {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.stage-legend i {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.legend-vsb { background: var(--cyan); }
.legend-active { background: var(--green); }
.legend-fire { background: var(--coral); }

.webgl-fallback {
  position: absolute;
  inset: 45% 1rem auto;
  color: var(--coral);
  text-align: center;
}

.inspector {
  display: flex;
  min-width: 0;
  flex-direction: column;
  overflow-y: auto;
  background: var(--panel);
}

.inspector section,
.detail-link {
  padding: 1rem;
  border-bottom: 1px solid var(--line);
}

.metric-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  padding: 0 !important;
  background: var(--line);
}

.metric-strip div {
  min-width: 0;
  padding: 0.85rem;
  background: var(--panel-2);
}

.metric-strip span,
.metric-strip strong {
  display: block;
}

.metric-strip span,
.eyebrow {
  margin: 0;
  color: #70838e;
  font-family: var(--mono);
  font-size: 0.61rem;
  text-transform: uppercase;
}

.metric-strip strong {
  margin-top: 0.2rem;
  font-family: var(--mono);
  font-size: 1.05rem;
}

.explanation > p:not(.eyebrow):not(.equation) {
  margin: 0.7rem 0 0;
  color: #c2ced4;
  font-size: 0.78rem;
  line-height: 1.58;
}

.equation {
  margin: 0.9rem 0 0;
  padding-left: 0.7rem;
  border-left: 2px solid var(--cyan);
  color: #7ee6f2;
  font-family: var(--mono);
  font-size: 0.68rem;
  line-height: 1.5;
}

.section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

#vsb-levels {
  overflow: hidden;
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 0.58rem;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.tile-list {
  display: grid;
  gap: 0.45rem;
  margin-top: 0.75rem;
}

.tile-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 3rem 3.2rem;
  align-items: center;
  gap: 0.55rem;
  min-width: 0;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.64rem;
}

.tile-row strong {
  overflow: hidden;
  color: #dbe7eb;
  font-weight: 600;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.tile-row .state {
  color: var(--cyan);
  text-align: right;
}

.tile-row .flag {
  color: #657982;
  text-align: right;
}

.tile-row.is-fire .flag { color: var(--coral); }
.tile-row.is-locked .flag { color: var(--green); }

.event-log {
  min-height: 116px;
  flex: 1;
}

.event-log ol {
  display: grid;
  gap: 0.4rem;
  margin: 0.7rem 0 0;
  padding: 0;
  list-style: none;
}

.event-log li {
  display: grid;
  grid-template-columns: 2.5rem minmax(0, 1fr);
  gap: 0.45rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.61rem;
  line-height: 1.4;
}

.event-log li time {
  color: var(--amber);
}

.detail-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text);
  font-size: 0.76rem;
  text-decoration: none;
}

.detail-link:hover {
  color: var(--cyan);
}

.controls {
  display: grid;
  grid-template-columns: auto minmax(180px, 1fr) minmax(180px, 1fr) auto;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1rem;
  border-top: 1px solid var(--line);
  background: #090e12;
}

.transport,
.speed {
  display: flex;
  align-items: center;
}

.transport {
  gap: 0.35rem;
}

.transport button {
  width: 34px;
  height: 34px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: var(--panel-2);
  color: var(--text);
  cursor: pointer;
}

.transport button:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.controls label {
  display: grid;
  grid-template-columns: auto minmax(70px, 1fr) 3.2rem;
  align-items: center;
  gap: 0.65rem;
  min-width: 0;
  color: var(--muted);
  font-size: 0.66rem;
}

.controls output {
  color: var(--text);
  font-family: var(--mono);
  text-align: right;
}

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

.speed {
  border: 1px solid var(--line);
  border-radius: 4px;
  overflow: hidden;
}

.speed button {
  height: 32px;
  padding: 0 0.65rem;
  border: 0;
  border-right: 1px solid var(--line);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 0.62rem;
}

.speed button:last-child {
  border-right: 0;
}

.speed button.is-active {
  background: var(--panel-2);
  color: var(--cyan);
}

@media (max-width: 980px) {
  .lab-main {
    grid-template-columns: 1fr;
  }

  .stage {
    min-height: 520px;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .inspector {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    overflow: visible;
  }

  .metric-strip,
  .detail-link {
    grid-column: 1 / -1;
  }

  .event-log {
    min-height: 0;
  }

  .controls {
    grid-template-columns: auto 1fr 1fr;
  }

  .speed {
    grid-column: 1 / -1;
    justify-self: stretch;
  }

  .speed button {
    flex: 1;
  }
}

@media (max-width: 640px) {
  .lab-shell {
    grid-template-rows: 48px auto auto auto;
  }

  .lab-header {
    padding: 0 0.75rem;
  }

  .runtime-state span,
  .header-separator + span {
    display: none;
  }

  .pattern-nav {
    grid-template-columns: repeat(6, 132px);
  }

  .stage {
    min-height: 430px;
  }

  .stage-title p {
    display: none;
  }

  .stage-legend {
    max-width: calc(100% - 2rem);
  }

  .inspector {
    grid-template-columns: 1fr;
  }

  .metric-strip,
  .detail-link {
    grid-column: auto;
  }

  .controls {
    grid-template-columns: 1fr;
    gap: 0.65rem;
  }

  .transport {
    justify-content: center;
  }

  .speed {
    grid-column: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
  }
}