:root {
  color-scheme: dark;
  --bg: #08111f;
  --bg-soft: #0d1b2e;
  --surface: rgba(255, 255, 255, 0.08);
  --surface-strong: rgba(255, 255, 255, 0.14);
  --text: #f7fbff;
  --muted: #b8c7d9;
  --accent: #7dd3fc;
  --accent-strong: #38bdf8;
  --accent-warm: #fbbf24;
  --line: rgba(255, 255, 255, 0.14);
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.35);
  --radius: 24px;
  --max-width: 1120px;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-block-size: 100vb;
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(56, 189, 248, 0.24), transparent 34rem),
    radial-gradient(circle at 80% 10%, rgba(251, 191, 36, 0.13), transparent 26rem),
    var(--bg);
  line-height: 1.6;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(to bottom, black, transparent 78%);
}

a {
  color: inherit;
}

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

:focus-visible {
  outline: 3px solid var(--accent-warm);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  inset-block-start: 1rem;
  inset-inline-start: 1rem;
  z-index: 10;
  padding: 0.75rem 1rem;
  color: #07101e;
  background: var(--accent-warm);
  border-radius: 999px;
  transform: translateY(-150%);
  transition: transform 180ms ease;
}

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

.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 5;
  border-block-end: 1px solid var(--line);
  background: rgba(8, 17, 31, 0.78);
  backdrop-filter: blur(18px);
}

.nav,
.section,
.site-footer {
  inline-size: min(100% - 2rem, var(--max-width));
  margin-inline: auto;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 1rem;
}

.brand,
.nav-links {
  display: flex;
  align-items: center;
}

.brand {
  gap: 0.75rem;
  font-weight: 800;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  inline-size: 2.35rem;
  block-size: 2.35rem;
  place-items: center;
  color: #06101e;
  background: linear-gradient(135deg, var(--accent), var(--accent-warm));
  border-radius: 0.85rem;
  box-shadow: 0 12px 30px rgba(125, 211, 252, 0.24);
}

.nav-links {
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.35rem;
  padding: 0;
  margin: 0;
  list-style: none;
}

.nav-links a {
  display: inline-flex;
  padding: 0.6rem 0.8rem;
  color: var(--muted);
  text-decoration: none;
  border-radius: 999px;
}

.nav-links a:hover {
  color: var(--text);
  background: var(--surface);
}

.section {
  padding-block: clamp(4rem, 8vw, 7rem);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(18rem, 0.65fr);
  align-items: center;
  gap: clamp(2rem, 6vw, 5rem);
  min-block-size: calc(100svb - 5rem);
}

.eyebrow,
.card-kicker,
.signal-label {
  margin-block: 0 0.75rem;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-block-start: 0;
}

h1,
h2,
h3 {
  line-height: 1.05;
  letter-spacing: -0.04em;
}

h1 {
  max-inline-size: 12ch;
  margin-block-end: 1.35rem;
  font-size: clamp(3.25rem, 10vw, 6.8rem);
}

h2 {
  max-inline-size: 13ch;
  margin-block-end: 1rem;
  font-size: clamp(2.15rem, 5vw, 4rem);
}

h3 {
  margin-block-end: 0.75rem;
  font-size: clamp(1.4rem, 3vw, 1.8rem);
}

.hero-text,
.intro p,
.split p,
.game-copy p,
.contact p {
  max-inline-size: 62ch;
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.25rem);
}

.hero-actions,
.contact {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-block-size: 2.85rem;
  padding: 0.75rem 1.1rem;
  font: inherit;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
  border: 1px solid transparent;
  border-radius: 999px;
}

.button-primary {
  color: #06101e;
  background: linear-gradient(135deg, var(--accent), var(--accent-warm));
  box-shadow: 0 18px 40px rgba(56, 189, 248, 0.22);
}

.button-secondary {
  color: var(--text);
  background: var(--surface);
  border-color: var(--line);
}

.button:hover {
  transform: translateY(-1px);
}

.signal-card,
.card,
.game-card,
.process-list li {
  border: 1px solid var(--line);
  background: linear-gradient(145deg, var(--surface-strong), rgba(255, 255, 255, 0.045));
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.signal-card {
  padding: clamp(1.25rem, 4vw, 2rem);
}

.signal-card strong {
  display: block;
  margin-block-end: 1.5rem;
  font-size: clamp(1.45rem, 3vw, 2rem);
  line-height: 1.1;
}

.signal-list {
  display: grid;
  gap: 1rem;
  margin: 0;
}

.signal-list div {
  padding-block-start: 1rem;
  border-block-start: 1px solid var(--line);
}

.signal-list dt {
  color: var(--muted);
  font-size: 0.85rem;
}

.signal-list dd {
  margin: 0;
  font-weight: 800;
}

.intro,
.split,
.game-section {
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(2rem, 6vw, 4rem);
}

.section-heading {
  margin-block-end: 2rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 16rem), 1fr));
  gap: 1rem;
}

.card {
  display: grid;
  align-content: start;
  min-block-size: 17rem;
  padding: 1.35rem;
}

.card p:last-child,
.process-list span {
  color: var(--muted);
}

.skill-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 14rem), 1fr));
  gap: 0.85rem;
  padding: 0;
  margin: 0;
  list-style: none;
}

.skill-list li {
  padding: 0.85rem 1rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 1rem;
}

.process-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  padding: 0;
  margin: 0;
  list-style-position: inside;
}

.process-list li {
  padding: 1.25rem;
}

.process-list strong,
.process-list span {
  display: block;
}

.process-list strong {
  margin-block: 0.6rem 0.4rem;
  font-size: 1.25rem;
}

.game-section {
  align-items: center;
}

.game-card {
  inline-size: min(100%, 28rem);
  justify-self: end;
  padding: clamp(1rem, 4vw, 1.5rem);
}

.game-status {
  min-block-size: 2rem;
  margin-block-end: 1rem;
  color: var(--accent-warm);
  font-weight: 800;
  text-align: center;
}

.board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.6rem;
}

.cell {
  display: grid;
  aspect-ratio: 1;
  place-items: center;
  color: var(--text);
  font: inherit;
  font-size: clamp(2.25rem, 10vw, 4rem);
  font-weight: 900;
  line-height: 1;
  cursor: pointer;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid var(--line);
  border-radius: 1.2rem;
}

.cell:not(:disabled):hover {
  background: rgba(125, 211, 252, 0.16);
}

.cell:disabled {
  cursor: not-allowed;
  opacity: 0.85;
}

.cell.winner {
  color: #06101e;
  background: linear-gradient(135deg, var(--accent), var(--accent-warm));
}

.reset-button {
  inline-size: 100%;
  margin-block-start: 1rem;
}

.contact {
  flex-direction: column;
  align-items: flex-start;
  padding: clamp(2rem, 6vw, 4rem);
  margin-block-end: 4rem;
  border: 1px solid var(--line);
  background: linear-gradient(135deg, rgba(125, 211, 252, 0.15), rgba(251, 191, 36, 0.08));
  border-radius: var(--radius);
}

.site-footer {
  padding-block: 2rem;
  color: var(--muted);
  border-block-start: 1px solid var(--line);
}

.site-footer p {
  margin: 0;
}

@media (max-width: 820px) {
  .hero,
  .intro,
  .split,
  .game-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-block-size: auto;
  }

  .game-card {
    justify-self: stretch;
  }

  .process-list {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 620px) {
  .nav {
    align-items: flex-start;
    flex-direction: column;
  }

  .nav-links {
    justify-content: flex-start;
  }

  .section {
    padding-block: 3.5rem;
  }
}

@media (prefers-color-scheme: light) {
  :root {
    color-scheme: light;
    --bg: #f5f8fc;
    --bg-soft: #eaf1f9;
    --surface: rgba(8, 17, 31, 0.06);
    --surface-strong: rgba(255, 255, 255, 0.78);
    --text: #08111f;
    --muted: #43566e;
    --line: rgba(8, 17, 31, 0.14);
    --shadow: 0 24px 80px rgba(8, 17, 31, 0.12);
  }

  body {
    background:
      radial-gradient(circle at top left, rgba(56, 189, 248, 0.22), transparent 34rem),
      radial-gradient(circle at 80% 10%, rgba(251, 191, 36, 0.18), transparent 26rem),
      var(--bg);
  }

  .site-header {
    background: rgba(245, 248, 252, 0.8);
  }
}

@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;
  }
}