:root {
  color-scheme: dark;
  --ink: #f4f7f3;
  --muted: #9fb3b5;
  --panel: rgba(14, 30, 39, 0.88);
  --panel-solid: #10252f;
  --line: rgba(187, 221, 216, 0.14);
  --accent: #ffcc66;
  --accent-strong: #ffb738;
  --mint: #76d6b2;
  --blue: #78b8ff;
  --danger: #ff8e7d;
  --road: #263642;
  --road-line: #e6c867;
  --grass-a: #467e58;
  --grass-b: #3c714f;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.3);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  min-height: 100%;
  background: #081219;
}

body {
  min-width: 320px;
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% 0%, rgba(51, 135, 125, 0.27), transparent 35rem),
    radial-gradient(circle at 100% 14%, rgba(45, 92, 135, 0.24), transparent 34rem),
    linear-gradient(150deg, #081219, #0b1720 55%, #071117);
}

button {
  font: inherit;
}

button:focus-visible,
a:focus-visible {
  outline: 3px solid #ffffff;
  outline-offset: 3px;
}

[hidden] {
  display: none !important;
}

.skip-link {
  position: fixed;
  z-index: 20;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.7rem 1rem;
  color: #071117;
  background: #ffffff;
  border-radius: 0.7rem;
  transform: translateY(-180%);
  transition: transform 160ms ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.traffic-lab {
  width: min(1440px, 100%);
  min-height: 100vh;
  margin: 0 auto;
  padding: clamp(1rem, 2.4vw, 2.5rem);
}

.traffic-lab__hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 2rem;
  align-items: end;
  padding: clamp(1.4rem, 3vw, 3rem);
  overflow: hidden;
  position: relative;
  border: 1px solid var(--line);
  border-radius: 1.6rem;
  background:
    linear-gradient(105deg, rgba(13, 32, 42, 0.96), rgba(13, 32, 42, 0.74)),
    repeating-linear-gradient(90deg, transparent 0 63px, rgba(255, 255, 255, 0.03) 63px 64px);
  box-shadow: var(--shadow);
}

.traffic-lab__hero::after {
  content: "";
  position: absolute;
  width: 20rem;
  height: 20rem;
  right: -7rem;
  top: -11rem;
  border: 2.5rem solid rgba(118, 214, 178, 0.08);
  border-radius: 50%;
  pointer-events: none;
}

.traffic-lab__intro {
  max-width: 52rem;
}

.eyebrow {
  margin: 0 0 0.65rem;
  color: var(--mint);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.16em;
}

.traffic-lab h1 {
  margin: 0;
  max-width: 10ch;
  font-size: clamp(2.5rem, 7vw, 6.2rem);
  line-height: 0.86;
  letter-spacing: -0.07em;
}

.traffic-lab__intro > p:last-child {
  max-width: 46rem;
  margin: 1.3rem 0 0;
  color: #c8d5d4;
  font-size: clamp(1rem, 1.6vw, 1.2rem);
  line-height: 1.55;
}

.traffic-lab__score {
  display: grid;
  grid-template-columns: repeat(3, minmax(5.6rem, 1fr));
  gap: 0.5rem;
  min-width: min(100%, 21rem);
  margin: 0;
  position: relative;
  z-index: 1;
}

.traffic-lab__score div {
  padding: 0.9rem;
  border: 1px solid rgba(255, 255, 255, 0.09);
  border-radius: 1rem;
  background: rgba(255, 255, 255, 0.055);
  backdrop-filter: blur(12px);
}

.traffic-lab__score dt,
.traffic-lab__metrics dt {
  color: var(--muted);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.traffic-lab__score dd {
  margin: 0.22rem 0 0;
  font-size: clamp(1.45rem, 3vw, 2.2rem);
  font-weight: 800;
  letter-spacing: -0.04em;
}

.traffic-lab__goals {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin: 1rem 0;
}

.traffic-lab__goals button {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0 0.9rem;
  align-items: center;
  min-height: 5.4rem;
  padding: 1rem 1.15rem;
  color: var(--ink);
  text-align: left;
  border: 1px solid var(--line);
  border-radius: 1.1rem;
  background: rgba(16, 37, 47, 0.78);
  cursor: pointer;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
}

.traffic-lab__goals button:hover {
  transform: translateY(-2px);
  border-color: rgba(118, 214, 178, 0.45);
}

.traffic-lab__goals button.is-active {
  color: #09151b;
  border-color: var(--accent);
  background: linear-gradient(135deg, var(--accent), #ffe3a4);
}

.traffic-lab__goals span {
  grid-row: 1 / 3;
  align-self: stretch;
  display: grid;
  place-items: center;
  min-width: 3rem;
  color: currentColor;
  font-weight: 900;
  border-right: 1px solid currentColor;
  opacity: 0.75;
}

.traffic-lab__goals strong {
  font-size: 1.05rem;
}

.traffic-lab__goals small {
  margin-top: 0.25rem;
  color: inherit;
  opacity: 0.7;
}

.traffic-lab__workspace {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(17rem, 21rem);
  gap: 1rem;
  align-items: start;
}

.traffic-lab__map-column,
.traffic-lab__control {
  border: 1px solid var(--line);
  border-radius: 1.4rem;
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(20px);
}

.traffic-lab__map-column {
  min-width: 0;
  padding: clamp(0.75rem, 2vw, 1.3rem);
}

.traffic-lab__toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  min-height: 3.25rem;
  padding: 0.25rem 0.25rem 0.9rem;
}

.traffic-lab__toolbar button,
.traffic-lab__speed button,
.traffic-lab__pause,
.traffic-lab__reset {
  color: var(--ink);
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.06);
  cursor: pointer;
}

.traffic-lab__toolbar button {
  flex: 1 1 auto;
  min-height: 2.7rem;
  padding: 0.55rem 0.9rem;
  border-radius: 0.75rem;
}

.traffic-lab__toolbar button:hover,
.traffic-lab__speed button:hover,
.traffic-lab__pause:hover,
.traffic-lab__reset:hover {
  border-color: rgba(255, 204, 102, 0.72);
}

.traffic-lab__toolbar button.is-active,
.traffic-lab__speed button.is-active {
  color: #111a1c;
  border-color: var(--accent);
  background: var(--accent);
  font-weight: 800;
}

.traffic-lab__toolbar--traffic {
  align-items: center;
  color: #c4d0d1;
  font-size: 0.9rem;
  line-height: 1.45;
}

.traffic-lab__map-frame {
  padding: clamp(0.35rem, 1vw, 0.75rem);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 1rem;
  background: #071117;
}

.traffic-lab__map {
  display: grid;
  grid-template-columns: repeat(8, minmax(0, 1fr));
  width: min(100%, 50rem);
  margin: 0 auto;
  overflow: hidden;
  border: 1px solid rgba(3, 13, 8, 0.52);
  border-radius: 0.65rem;
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.04);
}

.traffic-lab__cell {
  position: relative;
  aspect-ratio: 1;
  min-width: 0;
  padding: 0;
  overflow: hidden;
  border: 0;
  border-right: 1px solid rgba(4, 23, 12, 0.18);
  border-bottom: 1px solid rgba(4, 23, 12, 0.18);
  background:
    radial-gradient(circle at 28% 24%, rgba(255, 255, 255, 0.055) 0 3%, transparent 4%),
    linear-gradient(145deg, var(--grass-a), var(--grass-b));
  cursor: pointer;
  isolation: isolate;
}

.traffic-lab__cell::after {
  content: "";
  position: absolute;
  inset: 5%;
  z-index: 6;
  border: 2px solid transparent;
  border-radius: 0.35rem;
  pointer-events: none;
}

.traffic-lab__cell:hover::after {
  border-color: rgba(255, 255, 255, 0.48);
}

.traffic-lab__cell:focus-visible {
  outline: none;
}

.traffic-lab__cell:focus-visible::after {
  border-color: #ffffff;
  box-shadow: 0 0 0 3px #0b1720;
}

.traffic-lab__cell.is-road {
  background: var(--road);
}

.traffic-lab__road-core,
.traffic-lab__road-arm {
  position: absolute;
  z-index: 1;
  display: block;
  background:
    linear-gradient(90deg, transparent 47%, rgba(230, 200, 103, 0.88) 48% 52%, transparent 53%),
    #344753;
}

.traffic-lab__road-core {
  inset: 31%;
}

.traffic-lab__road-arm {
  display: none;
}

.traffic-lab__road-arm.is-n,
.traffic-lab__road-arm.is-s {
  left: 31%;
  width: 38%;
  height: 32%;
}

.traffic-lab__road-arm.is-e,
.traffic-lab__road-arm.is-w {
  top: 31%;
  width: 32%;
  height: 38%;
  background:
    linear-gradient(0deg, transparent 47%, rgba(230, 200, 103, 0.88) 48% 52%, transparent 53%),
    #344753;
}

.traffic-lab__road-arm.is-n { top: 0; }
.traffic-lab__road-arm.is-e { right: 0; }
.traffic-lab__road-arm.is-s { bottom: 0; }
.traffic-lab__road-arm.is-w { left: 0; }

.traffic-lab__cell[data-connections*="n"] .traffic-lab__road-arm.is-n,
.traffic-lab__cell[data-connections*="e"] .traffic-lab__road-arm.is-e,
.traffic-lab__cell[data-connections*="s"] .traffic-lab__road-arm.is-s,
.traffic-lab__cell[data-connections*="w"] .traffic-lab__road-arm.is-w {
  display: block;
}

.traffic-lab__cell.is-road[data-connections=""] .traffic-lab__road-core {
  inset: 18%;
  border-radius: 0.35rem;
}

.traffic-lab__cell.is-intersection .traffic-lab__road-core {
  inset: 24%;
  background: #3b4d57;
}

.traffic-lab__signal {
  position: absolute;
  z-index: 5;
  top: 10%;
  left: 10%;
  width: 17%;
  aspect-ratio: 1;
  border: 2px solid #0a1419;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.2), 0 0 12px rgba(255, 204, 102, 0.65);
}

.traffic-lab__signal.is-vertical {
  background: var(--blue);
  box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.2), 0 0 12px rgba(120, 184, 255, 0.7);
}

.traffic-lab__car {
  position: absolute;
  z-index: 4;
  width: 17%;
  height: 27%;
  border-radius: 30% 30% 22% 22%;
  background: #fff4d0;
  border: 1px solid rgba(0, 0, 0, 0.62);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.44);
  transform: translate(-50%, -50%) rotate(90deg);
}

.traffic-lab__car::before,
.traffic-lab__car::after {
  content: "";
  position: absolute;
  left: 16%;
  width: 68%;
  height: 17%;
  border-radius: 99px;
  background: #274250;
}

.traffic-lab__car::before { top: 18%; }
.traffic-lab__car::after { bottom: 18%; }
.traffic-lab__car.is-1 { background: #fff4d0; }
.traffic-lab__car.is-2 { background: #ff8e7d; }
.traffic-lab__car.is-3 { background: #78b8ff; }
.traffic-lab__car.is-dir-e { left: 48%; top: 42%; transform: translate(-50%, -50%) rotate(90deg); }
.traffic-lab__car.is-dir-w { left: 52%; top: 58%; transform: translate(-50%, -50%) rotate(-90deg); }
.traffic-lab__car.is-dir-n { left: 58%; top: 52%; transform: translate(-50%, -50%); }
.traffic-lab__car.is-dir-s { left: 42%; top: 48%; transform: translate(-50%, -50%) rotate(180deg); }
.traffic-lab__car.is-2.is-dir-e,
.traffic-lab__car.is-2.is-dir-w { left: 64%; }
.traffic-lab__car.is-2.is-dir-n,
.traffic-lab__car.is-2.is-dir-s { top: 34%; }
.traffic-lab__car.is-3.is-dir-e,
.traffic-lab__car.is-3.is-dir-w { left: 34%; }
.traffic-lab__car.is-3.is-dir-n,
.traffic-lab__car.is-3.is-dir-s { top: 66%; }

.traffic-lab__car.is-stopped {
  animation: queue-pulse 900ms ease-in-out infinite alternate;
}

.traffic-lab__building {
  position: absolute;
  z-index: 2;
  inset: 20% 22% 17%;
  display: block;
  border: 1px solid rgba(30, 43, 36, 0.52);
  border-radius: 0.22rem;
  background: linear-gradient(135deg, #f2d88f, #ce9b5a);
  box-shadow: 0.28rem 0.32rem 0 rgba(17, 48, 27, 0.32);
}

.traffic-lab__building::before {
  content: "";
  position: absolute;
  left: -9%;
  right: -9%;
  top: -21%;
  height: 42%;
  background: #bc655e;
  clip-path: polygon(50% 0, 100% 72%, 90% 100%, 10% 100%, 0 72%);
}

.traffic-lab__building-face {
  position: absolute;
  width: 24%;
  height: 34%;
  left: 38%;
  bottom: 0;
  background: #694b3b;
}

.traffic-lab__building--work {
  inset: 14% 24% 11%;
  border-radius: 0.18rem;
  background:
    repeating-linear-gradient(90deg, transparent 0 21%, rgba(221, 245, 255, 0.74) 22% 38%, transparent 39% 59%),
    linear-gradient(#769bb0, #486f85);
  box-shadow: 0.3rem 0.34rem 0 rgba(17, 48, 27, 0.32);
}

.traffic-lab__building--work::before {
  left: 8%;
  right: 8%;
  top: -10%;
  height: 11%;
  background: #b4cad3;
  clip-path: none;
}

.traffic-lab__building--work .traffic-lab__building-face {
  width: 32%;
  left: 34%;
  height: 19%;
  background: #193c50;
}

.traffic-lab__building-wing {
  position: absolute;
  width: 25%;
  height: 14%;
  left: 38%;
  top: -20%;
  background: #a9d8e7;
}

.traffic-lab__notice {
  min-height: 2.8rem;
  margin: 0.85rem 0 0;
  padding: 0.8rem 0.9rem;
  color: #d4dfde;
  border-left: 3px solid var(--mint);
  background: rgba(118, 214, 178, 0.06);
  line-height: 1.4;
}

.traffic-lab__control {
  position: sticky;
  top: 1rem;
  padding: 1.1rem;
}

.traffic-lab__control section {
  padding: 0.35rem 0 1rem;
  border-bottom: 1px solid var(--line);
}

.traffic-lab__control section + section {
  padding-top: 1rem;
}

.traffic-lab__metrics {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.5rem;
  margin: 0;
}

.traffic-lab__metrics div {
  min-width: 0;
  padding: 0.75rem;
  border-radius: 0.8rem;
  background: rgba(255, 255, 255, 0.045);
}

.traffic-lab__metrics div:nth-child(3) {
  grid-column: 1 / -1;
}

.traffic-lab__metrics dd {
  margin: 0.25rem 0 0;
  font-size: 1.25rem;
  font-weight: 800;
}

.traffic-lab__pause,
.traffic-lab__reset {
  width: 100%;
  min-height: 2.9rem;
  padding: 0.7rem 0.9rem;
  border-radius: 0.8rem;
}

.traffic-lab__speed {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.4rem;
  margin-top: 0.5rem;
}

.traffic-lab__speed button {
  min-height: 2.45rem;
  border-radius: 0.65rem;
}

.traffic-lab__legend p:not(.eyebrow) {
  display: flex;
  gap: 0.65rem;
  align-items: center;
  margin: 0.55rem 0;
  color: #c7d1d1;
  font-size: 0.86rem;
}

.traffic-lab__legend span {
  flex: 0 0 auto;
  width: 1.25rem;
  height: 1.25rem;
  border-radius: 0.3rem;
  background: var(--accent);
}

.traffic-lab__legend .is-work { background: var(--blue); }
.traffic-lab__legend .is-signal { width: 0.75rem; height: 0.75rem; border-radius: 50%; background: var(--mint); }

.traffic-lab__reset {
  margin-top: 1rem;
  color: #ffc5bd;
  border-color: rgba(255, 142, 125, 0.35);
}

.traffic-lab__reset[data-confirming] {
  color: #17110c;
  border-color: var(--danger);
  background: var(--danger);
  font-weight: 800;
}

.traffic-lab__storage {
  display: block;
  margin-top: 0.75rem;
  color: #879da0;
  line-height: 1.45;
}

.traffic-lab__footer {
  padding: 1.2rem 0.3rem 0;
  color: #73898c;
  font-size: 0.78rem;
  text-align: center;
}

@keyframes queue-pulse {
  from { filter: brightness(1); }
  to { filter: brightness(1.5); }
}

@media (max-width: 960px) {
  .traffic-lab__hero {
    grid-template-columns: 1fr;
    align-items: start;
  }

  .traffic-lab__score {
    width: 100%;
  }

  .traffic-lab__workspace {
    grid-template-columns: 1fr;
  }

  .traffic-lab__control {
    position: static;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1rem;
  }

  .traffic-lab__control section {
    border-bottom: 0;
  }

  .traffic-lab__reset,
  .traffic-lab__storage {
    align-self: end;
  }
}

@media (max-width: 640px) {
  .traffic-lab {
    padding: 0.65rem;
  }

  .traffic-lab__hero {
    padding: 1.25rem;
    border-radius: 1.15rem;
  }

  .traffic-lab h1 {
    font-size: clamp(2.65rem, 15vw, 4.6rem);
  }

  .traffic-lab__score {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    min-width: 0;
  }

  .traffic-lab__score div {
    min-width: 0;
    padding: 0.65rem 0.5rem;
  }

  .traffic-lab__score dt {
    font-size: 0.62rem;
  }

  .traffic-lab__goals {
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }

  .traffic-lab__goals button {
    min-height: 4.5rem;
  }

  .traffic-lab__map-column {
    padding: 0.55rem;
  }

  .traffic-lab__toolbar button {
    flex-basis: calc(50% - 0.5rem);
  }

  .traffic-lab__map-frame {
    padding: 0.22rem;
  }

  .traffic-lab__control {
    grid-template-columns: 1fr;
  }

  .traffic-lab__cell::after {
    inset: 3%;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}