:root {
  color-scheme: dark;
  --bg: #090b0d;
  --panel: #101418;
  --line: #273038;
  --text: #f3f6f7;
  --muted: #91a0aa;
  --accent: #69ef9a;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--bg); }
body { margin: 0; color: var(--text); background: radial-gradient(circle at 72% -8%, rgba(105,239,154,.09), transparent 31rem), var(--bg); min-height: 100vh; }
a { color: inherit; }
.site-header { min-height: 72px; padding: 0 clamp(20px, 5vw, 72px); border-bottom: 1px solid var(--line); display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { color: var(--text); text-decoration: none; font-weight: 780; letter-spacing: .13em; font-size: .82rem; display: inline-flex; align-items: center; gap: 11px; }
.pulse-mark { width: 14px; height: 14px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 22px rgba(105,239,154,.7); flex: none; }
nav { display: flex; gap: clamp(18px, 3vw, 38px); margin-left: auto; }
nav a { color: var(--muted); text-decoration: none; font-size: .78rem; }
nav a:hover, nav a:focus-visible { color: var(--accent); }
.language-control select { height: 34px; min-width: 66px; color: #c8d1d6; background: #0d1013; border: 1px solid var(--line); border-radius: 999px; padding: 0 10px; font: 700 .7rem ui-monospace, monospace; cursor: pointer; }
.language-control select:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

main, footer { width: min(1420px, calc(100% - 40px)); margin: 0 auto; }
.hero { min-height: min(780px, calc(100vh - 72px)); padding: clamp(76px, 11vw, 148px) 0 54px; position: relative; display: flex; flex-direction: column; justify-content: center; border-bottom: 1px solid var(--line); overflow: hidden; }
.hero > :not(.globe-stage) { position: relative; z-index: 2; }
.eyebrow, .card-label { margin: 0 0 18px; color: var(--accent); text-transform: uppercase; letter-spacing: .16em; font-weight: 730; font-size: .71rem; }
h1 { max-width: 1150px; margin: 0; font-size: clamp(3.4rem, 8vw, 8.1rem); letter-spacing: -.068em; line-height: .9; font-weight: 760; }
h1 span { color: #74818a; }
h1 .hero-primary { color: var(--text); }
.hero-foot { margin-top: clamp(38px, 6vw, 74px); display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 50px; align-items: end; }
.hero-foot p { max-width: 680px; margin: 0; color: #aab5bb; font-size: clamp(1rem, 1.35vw, 1.2rem); line-height: 1.65; }
.primary-link { text-decoration: none; border: 1px solid #3b4841; background: rgba(105,239,154,.08); color: var(--accent); border-radius: 999px; padding: 14px 20px; font-size: .85rem; white-space: nowrap; }
.primary-link:hover, .primary-link:focus-visible { background: rgba(105,239,154,.15); border-color: var(--accent); }
.globe-stage { position: absolute; z-index: 1; right: -3%; top: 4%; width: min(46vw, 650px); aspect-ratio: 1; opacity: .82; pointer-events: none; -webkit-mask-image: radial-gradient(circle, #000 58%, transparent 76%); mask-image: radial-gradient(circle, #000 58%, transparent 76%); }
.globe-stage canvas { width: 100%; height: 100%; display: block; }

.games, .principles, .measurement { padding: clamp(80px, 10vw, 140px) 0; border-bottom: 1px solid var(--line); }
.section-heading { display: grid; grid-template-columns: 1fr minmax(280px, 520px); gap: 50px; align-items: end; margin-bottom: 50px; }
.section-heading.compact { grid-template-columns: 1fr; }
h2 { margin: 0; max-width: 880px; font-size: clamp(2.5rem, 5vw, 5.2rem); letter-spacing: -.058em; line-height: .98; }
.section-heading > p { margin: 0; color: var(--muted); line-height: 1.65; }
.game-card { min-height: 260px; padding: clamp(24px, 4vw, 52px); display: grid; grid-template-columns: 70px minmax(260px, 1fr) auto 40px; gap: clamp(20px, 4vw, 58px); align-items: center; text-decoration: none; border: 1px solid var(--line); border-radius: 16px; background: linear-gradient(115deg, rgba(105,239,154,.08), rgba(16,20,24,.86) 55%); transition: border-color .2s ease, transform .2s ease; }
.game-card:hover, .game-card:focus-visible { border-color: rgba(105,239,154,.65); transform: translateY(-2px); outline: none; }
.game-card + .game-card { margin-top: 16px; }
.game-index { color: #56636b; font: 700 .72rem ui-monospace, monospace; }
.game-card h3 { margin: 0; font-size: clamp(3.2rem, 6vw, 6.5rem); letter-spacing: -.06em; line-height: .9; }
.game-card p:last-child { max-width: 600px; color: var(--muted); line-height: 1.55; margin: 22px 0 0; }
.game-state { color: #c6d1d6; font-size: .78rem; display: flex; align-items: center; gap: 9px; white-space: nowrap; }
.game-state span { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 13px rgba(105,239,154,.65); }
.arrow { color: var(--accent); font-size: 1.6rem; }
.next-game { display: flex; justify-content: space-between; gap: 30px; padding: 25px 4px 0; color: #64727a; font-size: .78rem; }
.principle-grid { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--line); border-radius: 16px; overflow: hidden; }
.principle-grid article { min-height: 280px; padding: clamp(28px, 4vw, 48px); background: rgba(16,20,24,.62); }
.principle-grid article + article { border-left: 1px solid var(--line); }
.principle-grid article > span { color: var(--accent); font: 700 .68rem ui-monospace, monospace; }
.principle-grid h3 { margin: 76px 0 15px; font-size: 1.7rem; letter-spacing: -.035em; }
.principle-grid p { color: var(--muted); margin: 0; max-width: 340px; line-height: 1.65; }
.measurement { display: grid; grid-template-columns: minmax(280px, .9fr) 1.1fr; gap: clamp(50px, 9vw, 150px); }
.measurement h2 { font-size: clamp(2.4rem, 4.5vw, 4.8rem); }
.steps { border-top: 1px solid var(--line); }
.steps div { padding: 27px 0; border-bottom: 1px solid var(--line); display: grid; grid-template-columns: 110px 1fr; gap: 24px; }
.steps span { color: var(--accent); text-transform: uppercase; letter-spacing: .13em; font-size: .66rem; }
.steps strong { font-size: 1rem; font-weight: 590; color: #c8d1d6; }
footer { padding: 34px 0 54px; color: #65727a; display: grid; grid-template-columns: 1fr auto auto; gap: 28px; align-items: center; font-size: .75rem; }
footer p { margin: 0; }
.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; }

@media (max-width: 880px) {
  .hero-foot, .section-heading, .measurement { grid-template-columns: 1fr; }
  .game-card { grid-template-columns: 48px 1fr 34px; }
  .game-state { grid-column: 2; }
  .arrow { grid-column: 3; grid-row: 1 / span 2; }
  .principle-grid { grid-template-columns: 1fr; }
  .principle-grid article { min-height: auto; }
  .principle-grid article + article { border-left: 0; border-top: 1px solid var(--line); }
  .principle-grid h3 { margin-top: 35px; }
  .globe-stage { right: -18%; top: 8%; width: min(68vw, 560px); opacity: .48; }
}

@media (max-width: 600px) {
  main, footer { width: min(100% - 28px, 1420px); }
  .site-header { padding: 0 14px; }
  nav { display: none; }
  .hero { min-height: auto; }
  h1 { font-size: clamp(3rem, 16vw, 5rem); }
  .globe-stage { display: none; }
  .game-card { grid-template-columns: 1fr 28px; }
  .game-index { display: none; }
  .game-state { grid-column: 1; }
  .arrow { grid-column: 2; grid-row: 1 / span 2; }
  .next-game { flex-direction: column; gap: 8px; }
  .steps div { grid-template-columns: 80px 1fr; }
  footer { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: no-preference) {
  .pulse-mark { animation: pulse 2.8s ease-in-out infinite; }
  @keyframes pulse { 50% { box-shadow: 0 0 30px rgba(105,239,154,.9); transform: scale(1.08); } }
}