/* Shared verbatim by Kinetica, React, Compose HTML, and Vanilla implementations. */
:root {
  color-scheme: dark;
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  font-synthesis: none;
  background: #070a12;
  color: #f4f7ff;
  --canvas: #070a12;
  --surface: #101624;
  --surface-raised: #151d2e;
  --surface-soft: #1a2335;
  --border: #28344a;
  --border-bright: #3d4f6d;
  --text: #f4f7ff;
  --muted: #96a4bb;
  --muted-bright: #bac5d7;
  --mint: #7cf7c8;
  --mint-deep: #2ccf9b;
  --blue: #87a8ff;
  --amber: #ffc876;
  --shadow: 0 30px 90px rgb(0 0 0 / 34%);
}

* {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  min-height: 100%;
  background: var(--canvas);
}

body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 8% 4%, rgb(70 103 181 / 19%), transparent 34rem),
    radial-gradient(circle at 94% 15%, rgb(44 207 155 / 10%), transparent 28rem),
    linear-gradient(180deg, #0a0e18 0%, #070a12 62%, #090d16 100%);
}

body::before {
  position: fixed;
  z-index: -1;
  inset: 0;
  background-image:
    linear-gradient(rgb(255 255 255 / 1.8%) 1px, transparent 1px),
    linear-gradient(90deg, rgb(255 255 255 / 1.8%) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: linear-gradient(to bottom, black, transparent 78%);
  content: "";
  pointer-events: none;
}

button {
  font: inherit;
}

button:focus-visible {
  outline: 3px solid rgb(135 168 255 / 75%);
  outline-offset: 3px;
}

noscript {
  display: block;
  padding: 2rem;
  color: var(--muted-bright);
  text-align: center;
}

.life-app {
  width: min(1380px, 100%);
  min-height: 100vh;
  margin: 0 auto;
  padding: 34px clamp(18px, 3vw, 48px) 48px;
}

.hero {
  margin-bottom: 26px;
  padding: 0 2px;
}

.brand-line {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 18px;
}

.brand-mark {
  display: grid;
  width: 30px;
  height: 30px;
  border: 1px solid rgb(124 247 200 / 48%);
  border-radius: 9px;
  background: linear-gradient(145deg, rgb(124 247 200 / 18%), rgb(135 168 255 / 12%));
  color: var(--mint);
  font-weight: 800;
  font-size: 14px;
  box-shadow: inset 0 1px rgb(255 255 255 / 10%), 0 8px 22px rgb(44 207 155 / 8%);
  place-items: center;
}

.eyebrow,
.section-kicker {
  color: var(--muted-bright);
  font-weight: 700;
  font-size: 11px;
  line-height: 1;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.rule-chip {
  margin-left: auto;
  padding: 7px 11px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: rgb(16 22 36 / 75%);
  color: var(--mint);
  font: 700 11px/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  letter-spacing: 0.08em;
}

.hero-copy {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 30px;
}

.hero h1 {
  margin: 0;
  color: var(--text);
  font-weight: 690;
  font-size: clamp(36px, 5vw, 66px);
  line-height: 0.98;
  letter-spacing: -0.052em;
}

.hero-copy p {
  width: min(420px, 100%);
  margin: 0 0 4px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.65;
}

.workspace {
  display: grid;
  grid-template-columns: 272px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
}

.preset-panel,
.simulation-panel {
  border: 1px solid var(--border);
  border-radius: 20px;
  background: rgb(16 22 36 / 92%);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.preset-panel {
  position: sticky;
  top: 18px;
  overflow: hidden;
  padding: 22px;
}

.section-heading {
  padding: 2px 2px 18px;
}

.section-heading h2 {
  margin: 8px 0 8px;
  font-weight: 680;
  font-size: 21px;
  letter-spacing: -0.025em;
}

.section-heading p {
  margin: 0;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.55;
}

.preset-list {
  display: grid;
  gap: 8px;
}

.preset-option {
  position: relative;
}

.preset-option::before {
  position: absolute;
  z-index: 1;
  top: 12px;
  bottom: 12px;
  left: 0;
  width: 3px;
  border-radius: 999px;
  background: transparent;
  content: "";
  transition: background 160ms ease, box-shadow 160ms ease;
}

.preset-option.is-selected::before {
  background: var(--mint);
  box-shadow: 0 0 16px rgb(124 247 200 / 52%);
}

.preset-option > button {
  display: flex;
  width: 100%;
  min-height: 96px;
  flex-direction: column;
  gap: 5px;
  align-items: stretch;
  padding: 13px 13px 12px 15px;
  border: 1px solid transparent;
  border-radius: 12px;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  text-align: left;
  transition: border-color 160ms ease, background 160ms ease, transform 160ms ease;
}

.preset-option > button:hover {
  border-color: var(--border);
  background: var(--surface-soft);
  transform: translateX(2px);
}

.preset-option.is-selected > button {
  border-color: rgb(124 247 200 / 18%);
  background: linear-gradient(90deg, rgb(124 247 200 / 10%), rgb(124 247 200 / 2%));
}

.preset-title {
  display: flex;
  gap: 8px;
  align-items: baseline;
  justify-content: space-between;
  font-weight: 700;
  font-size: 13px;
}

.preset-size {
  flex: 0 0 auto;
  color: var(--muted);
  font: 600 9px/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

.preset-category {
  color: var(--mint);
  font-weight: 700;
  font-size: 9px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.preset-description {
  color: var(--muted);
  font-size: 10px;
  line-height: 1.45;
}

.tip-card {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  margin-top: 18px;
  padding: 13px;
  border: 1px solid rgb(135 168 255 / 18%);
  border-radius: 12px;
  background: rgb(135 168 255 / 7%);
}

.tip-icon {
  color: var(--blue);
  line-height: 1.3;
}

.tip-card p {
  margin: 0;
  color: var(--muted-bright);
  font-size: 10px;
  line-height: 1.5;
}

.simulation-panel {
  overflow: hidden;
  min-width: 0;
}

.control-bar {
  display: grid;
  grid-template-columns: auto auto 1fr;
  gap: 12px;
  align-items: center;
  padding: 16px 18px;
  border-bottom: 1px solid var(--border);
  background: rgb(21 29 46 / 70%);
}

.primary-actions,
.secondary-actions,
.speed-options {
  display: flex;
  gap: 7px;
  align-items: center;
}

.control-bar button {
  min-height: 36px;
  padding: 0 13px;
  border: 1px solid var(--border-bright);
  border-radius: 9px;
  background: var(--surface-soft);
  color: var(--muted-bright);
  font-weight: 680;
  font-size: 11px;
  cursor: pointer;
  transition: border-color 150ms ease, background 150ms ease, color 150ms ease, transform 150ms ease;
}

.control-bar button:hover:not(:disabled) {
  border-color: #5b7095;
  background: #222e44;
  color: var(--text);
  transform: translateY(-1px);
}

.control-bar button:disabled {
  cursor: not-allowed;
  opacity: 0.38;
}

.primary-actions [data-testid="toggle-running"] {
  min-width: 88px;
  border-color: rgb(124 247 200 / 34%);
  background: var(--mint);
  color: #071811;
  box-shadow: 0 8px 24px rgb(44 207 155 / 15%);
}

.primary-actions [data-testid="toggle-running"]:hover:not(:disabled) {
  border-color: var(--mint);
  background: #96fbd5;
  color: #071811;
}

.button-icon {
  display: inline-block;
  min-width: 13px;
  margin-right: 6px;
  font-size: 10px;
  text-align: center;
}

.speed-control {
  display: flex;
  gap: 9px;
  align-items: center;
  justify-self: end;
}

.speed-label {
  color: var(--muted);
  font-weight: 700;
  font-size: 9px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.speed-options {
  gap: 3px;
  padding: 3px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: #0d1320;
}

.speed-options button {
  min-height: 27px;
  padding: 0 9px;
  border: 0;
  border-radius: 6px;
  background: transparent;
  font-size: 9px;
}

.speed-options button:disabled {
  background: var(--surface-soft);
  color: var(--mint);
  cursor: default;
  opacity: 1;
}

.status-strip {
  display: grid;
  grid-template-columns: repeat(2, minmax(82px, auto)) minmax(120px, 1fr) auto;
  gap: 0;
  align-items: center;
  min-height: 70px;
  padding: 0 20px;
  border-bottom: 1px solid var(--border);
}

.status-item {
  display: grid;
  gap: 3px;
  padding-right: 26px;
}

.status-label {
  color: var(--muted);
  font-weight: 700;
  font-size: 8px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.status-item strong,
.status-item .status-value {
  font-weight: 690;
  font-size: 15px;
  letter-spacing: -0.015em;
}

.pattern-status strong,
.pattern-status .status-value {
  overflow: hidden;
  color: var(--muted-bright);
  font-size: 12px;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.run-state {
  display: flex;
  gap: 8px;
  align-items: center;
  justify-self: end;
  color: var(--muted-bright);
  font-weight: 680;
  font-size: 10px;
}

.state-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #637087;
  box-shadow: 0 0 0 4px rgb(99 112 135 / 10%);
}

.state-dot.is-running {
  background: var(--mint);
  box-shadow: 0 0 0 4px rgb(124 247 200 / 10%), 0 0 18px rgb(124 247 200 / 65%);
  animation: breathe 1.2s ease-in-out infinite;
}

.board-frame {
  padding: clamp(12px, 2.2vw, 24px);
  background:
    radial-gradient(circle at center, rgb(34 50 76 / 16%), transparent 68%),
    #0b101b;
}

.board-chrome {
  overflow: hidden;
  border: 1px solid #2d3b53;
  border-radius: 14px;
  background: #080d17;
  box-shadow: inset 0 1px rgb(255 255 255 / 4%), 0 20px 46px rgb(0 0 0 / 24%);
}

.board-caption {
  display: flex;
  min-height: 38px;
  align-items: center;
  justify-content: space-between;
  padding: 0 13px;
  border-bottom: 1px solid #202b3e;
  color: var(--muted-bright);
  font: 650 9px/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.coordinate-hint {
  color: #687790;
  font-weight: 560;
  font-size: 8px;
  letter-spacing: 0.03em;
  text-transform: none;
}

.board-scroll {
  overflow-x: auto;
  padding: clamp(10px, 1.7vw, 18px);
  scrollbar-color: #3d4f6d #0b101b;
  scrollbar-width: thin;
}

.life-grid {
  display: grid;
  width: 100%;
  min-width: 1080px;
  grid-template-columns: repeat(72, minmax(0, 1fr));
  gap: 1px;
  padding: 2px;
  border-radius: 5px;
  background: #0e1625;
}

.life-cell {
  position: relative;
  width: 100%;
  min-width: 0;
  padding: 0;
  border: 0;
  border-radius: 2px;
  aspect-ratio: 1;
  background: #151e2e;
  box-shadow: inset 0 0 0 1px rgb(255 255 255 / 1.6%);
  cursor: crosshair;
  transition: background 90ms ease, box-shadow 90ms ease, transform 90ms ease;
}

.life-cell:hover {
  z-index: 1;
  background: #25344c;
  box-shadow: inset 0 0 0 1px rgb(135 168 255 / 32%), 0 0 0 1px rgb(135 168 255 / 18%);
  transform: scale(1.16);
}

.life-cell.is-alive {
  background: linear-gradient(145deg, #a6ffdf 4%, var(--mint) 45%, #4be3af 100%);
  box-shadow:
    inset 0 1px 1px rgb(255 255 255 / 48%),
    0 0 8px rgb(124 247 200 / 36%);
  animation: cell-born 160ms ease-out;
}

.life-cell.is-alive:hover {
  background: #c3ffea;
  box-shadow: 0 0 12px rgb(124 247 200 / 58%);
}

.life-cell:focus-visible {
  z-index: 2;
  outline: 2px solid var(--blue);
  outline-offset: 1px;
  transform: scale(1.18);
}

.rule-legend {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  border-top: 1px solid var(--border);
  background: var(--border);
}

.rule-legend > div {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 10px;
  align-items: center;
  min-height: 62px;
  padding: 12px 16px;
  background: var(--surface);
}

.legend-number {
  display: grid;
  min-width: 31px;
  height: 31px;
  padding: 0 5px;
  border: 1px solid rgb(124 247 200 / 25%);
  border-radius: 9px;
  background: rgb(124 247 200 / 8%);
  color: var(--mint);
  font: 750 11px/1 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  place-items: center;
}

.legend-number.muted-number {
  min-width: 61px;
  border-color: var(--border);
  background: var(--surface-soft);
  color: var(--muted-bright);
}

.rule-legend p {
  margin: 0;
  color: var(--muted);
  font-size: 9px;
  line-height: 1.4;
}

@keyframes cell-born {
  from {
    opacity: 0.42;
    transform: scale(0.55);
  }

  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes breathe {
  50% {
    box-shadow: 0 0 0 6px rgb(124 247 200 / 4%), 0 0 22px rgb(124 247 200 / 75%);
  }
}

@media (max-width: 1040px) {
  .workspace {
    grid-template-columns: 1fr;
  }

  .preset-panel {
    position: static;
  }

  .preset-list {
    grid-template-columns: repeat(2, 1fr);
  }

  .tip-card {
    max-width: 470px;
  }
}

@media (max-width: 760px) {
  .life-app {
    padding: 22px 12px 30px;
  }

  .hero-copy {
    display: block;
  }

  .hero-copy p {
    margin-top: 16px;
  }

  .preset-panel,
  .simulation-panel {
    border-radius: 16px;
  }

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

  .primary-actions {
    grid-column: 1;
  }

  .secondary-actions {
    grid-column: 2;
    justify-self: end;
  }

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

  .status-strip {
    grid-template-columns: repeat(2, 1fr);
    gap: 14px 0;
    padding-block: 15px;
  }

  .run-state {
    justify-self: start;
  }

  .rule-legend {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 520px) {
  .preset-list {
    grid-template-columns: 1fr;
  }

  .control-bar {
    display: flex;
    flex-wrap: wrap;
  }

  .primary-actions,
  .secondary-actions {
    width: 100%;
  }

  .primary-actions button,
  .secondary-actions button {
    flex: 1;
  }

  .coordinate-hint {
    display: none;
  }

  .board-frame {
    padding: 8px;
  }
}

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