:root {
  color-scheme: dark;
  --navy: #061824; --surface: #0a202e; --text: #f1f1e9; --muted: #adbdc6; --gold: #e7bf72; --line: #354b57; --error: #ffaea1;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--navy); color: var(--text); font-synthesis: none; text-rendering: optimizeLegibility; -webkit-text-size-adjust: 100%;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; font-size: 1rem; line-height: 1.7; }
button { font: inherit; color: inherit; }
a { color: inherit; text-underline-offset: .3em; }
a:hover { color: var(--gold); }
button, summary, a { -webkit-tap-highlight-color: transparent; }
:is(a,button,summary,[tabindex]):focus-visible { outline: 2px solid var(--gold); outline-offset: 4px; }
::selection { background: var(--gold); color: var(--navy); }
img { display: block; max-width: 100%; height: auto; }
h1,h2,h3,p,dt,dd,a,summary { overflow-wrap: break-word; }
h1,h2,h3 { font-weight: 550; letter-spacing: -.035em; }
h2 { font-size: clamp(1.65rem, 3vw, 2.2rem); line-height: 1.25; margin: 0; }
h3 { font-size: 1.2rem; line-height: 1.4; margin: 0; }
p { margin: 0; }
.page-shell { width: min(100% - 40px, 1120px); margin-inline: auto; }
.site-header { min-height: 92px; display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 8px 20px; border-bottom: 1px solid var(--line); position: relative; z-index: 5; }
.brand { min-height: 48px; display: inline-flex; gap: 10px; align-items: center; font-size: 1.35rem; font-weight: 600; text-decoration: none; letter-spacing: -.025em; }
.brand-icon { width: 44px; height: 44px; flex: none; display: grid; place-content: center; overflow: hidden; }
.brand-icon img { width: 80px; height: 60px; max-width: none; }
.primary-navigation { width: 100%; display: flex; flex-wrap: wrap; gap: 0 22px; padding-block: 8px 18px; }
.primary-navigation a { color: var(--muted); font-size: .875rem; display: flex; align-items: center; min-height: 44px; text-decoration: none; }
.primary-navigation a:hover, .primary-navigation a[aria-current="page"] { color: var(--gold); }
.menu-toggle { display: none; min-height: 44px; background: transparent; border: 1px solid var(--line); padding: 6px 12px; align-items: center; gap: 14px; cursor: pointer; font-size: .875rem; }
.menu-toggle span { color: var(--gold); font-size: 1.25rem; line-height: 1; }
.js .menu-toggle { display: flex; }
.js .primary-navigation { display: none; }
.js .primary-navigation.is-open { display: grid; }
.hero { display: grid; gap: 42px; padding-block: 56px 64px; }
.hero h1 { font-size: clamp(2.8rem, 5.4vw, 4.5rem); line-height: 1.07; margin: 0 0 24px; }
.hero h1 span { color: var(--gold); }
.intro { color: var(--muted); font-size: 1.0625rem; max-width: 35ch; line-height: 1.85; margin-bottom: 24px; }
.text-link { display: inline-flex; align-items: center; gap: 12px; min-height: 44px; color: var(--gold); font-size: .9375rem; }
.text-link span { flex: none; }
.demo { max-width: 366px; width: 100%; justify-self: center; }
.demo-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 8px; flex-wrap: wrap; margin-bottom: 8px; }
.demo-heading h2 { font-size: 1rem; letter-spacing: 0; }
.demo-heading > span { color: var(--muted); font-size: .75rem; }
.demo-instructions { font-size: .8125rem; color: var(--muted); margin-bottom: 18px; max-width: 43ch; }
.demo-board { width: 100%; aspect-ratio: 1; position: relative; display: grid; grid-template-columns: repeat(4,minmax(0,1fr)); grid-template-rows: repeat(4,minmax(0,1fr)); padding: 6px; border: 1px solid var(--line); background: var(--surface); }
.demo-cell { border: 0; background: transparent; position: relative; padding: 0; min-width: 0; cursor: pointer; }
.demo-cell::before { content: ""; position: absolute; inset: 0; background: url('./assets/cell_frame.png') center / contain no-repeat; pointer-events: none; }
.demo-cell[data-fixed="1"]::before { background-image: url('./assets/cell_fixed_gold.png'); }
.demo-cell[data-fixed="2"]::before { background-image: url('./assets/cell_fixed_cyan.png'); }
.demo-cell[aria-disabled="true"] { cursor: default; }
.demo-cell:focus-visible { outline-offset: -7px; z-index: 3; }
.demo-cell[aria-invalid="true"]::after { content: ""; position: absolute; inset: 7px; border: 2px solid var(--error); pointer-events: none; }
.demo-cell img { position: absolute; width: 85%; height: 85%; object-fit: contain; inset: 7.5%; pointer-events: none; }
.demo-cell img[hidden] { display: none; }
.fixed-label { position: absolute; bottom: 9%; left: 0; right: 0; font-size: 8px; color: var(--gold); line-height: 1; }
.demo-relation { position: absolute; width: 10%; height: 10%; transform: translate(-50%,-50%); z-index: 4; pointer-events: none; }
.demo-relation.equal { left: calc(25% + 3px); top: calc(12.5% + 4.5px); }
.demo-relation.different { left: calc(62.5% - 1.5px); top: calc(25% + 3px); }
.demo-footer { display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; margin-top: 10px; }
#demo-status { color: var(--muted); font-size: .75rem; padding-top: 10px; }
#demo-status[data-state="invalid"] { color: var(--error); }
#demo-status[data-state="complete"] { color: var(--gold); }
.reset-button { min-height: 44px; padding: 5px 0 5px 10px; border: 0; background: transparent; color: var(--gold); text-decoration: underline; text-underline-offset: .3em; font-size: .8125rem; cursor: pointer; flex: none; }
.demo-board.is-complete { border-color: var(--gold); animation: balance-pulse 700ms ease-out 1; }
@keyframes balance-pulse { 35% { background-color: #334036; } }
.section { padding-block: 58px; border-top: 1px solid var(--line); scroll-margin-top: 24px; }
.section-intro > p, .section-heading > p { color: var(--muted); font-size: .9375rem; max-width: 34ch; margin-top: 18px; }
.rule-list { margin-top: 30px; }
.rule { display: grid; gap: 22px; padding-block: 26px; border-bottom: 1px solid var(--line); }
.rule:last-child { border: 0; padding-bottom: 0; }
.rule-copy p { color: var(--muted); font-size: .9375rem; margin-top: 8px; }
.rule-copy strong { font-weight: 650; color: var(--text); }
.mini-line, .relation-examples, .relation-example { display: flex; align-items: center; }
.mini-line { gap: 4px; }
.mini-cell { width: 46px; height: 46px; flex: none; background: url('./assets/cell_frame.png') center / contain no-repeat; position: relative; }
.mini-cell::after { content: ""; position: absolute; inset: 5%; background: center / contain no-repeat; }
.mini-cell.fire::after { background-image: url('./assets/fire.png'); }
.mini-cell.water::after { background-image: url('./assets/water.png'); }
.invalid-example { border-bottom: 2px solid var(--error); padding-bottom: 4px; width: fit-content; }
.example-note { font-size: .75rem; color: var(--error); display: block; margin-top: 6px; }
.relation-examples { flex-wrap: wrap; gap: 12px 24px; }
.mini-relation { width: 28px; height: 28px; flex: none; margin-inline: -5px; z-index: 1; }
.section-heading { margin-bottom: 30px; }
.world { display: grid; gap: 24px; padding-block: 16px 36px; }
.world:last-child { padding-block: 30px 0; border-top: 1px solid var(--line); }
.world-image { width: 100%; height: auto; }
.world-copy h3 { font-size: 1.55rem; margin-bottom: 12px; }
.world-copy p { color: var(--muted); font-size: .9375rem; max-width: 38ch; }
.world-chapters { display: inline-block; color: var(--gold); font-size: .8125rem; margin-top: 18px; }
.mode-list { margin: 28px 0 0; }
.mode-list > div { display: grid; gap: 8px; padding-block: 20px; border-bottom: 1px solid var(--line); }
.mode-list > div:first-child { padding-top: 0; }
.mode-list > div:last-child { border: 0; padding-bottom: 0; }
.mode-list dt { font-size: 1.05rem; font-weight: 550; }
.mode-list dd { margin: 0; color: var(--muted); font-size: .9375rem; }
.faq-list { margin-top: 24px; }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { padding-block: 20px; cursor: pointer; min-height: 44px; list-style: none; display: flex; justify-content: space-between; align-items: center; gap: 20px; font-size: .9375rem; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; color: var(--gold); font-size: 1.25rem; flex: none; }
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { padding: 0 24px 22px 0; color: var(--muted); font-size: .9375rem; }
.support { border-top: 1px solid var(--line); display: grid; gap: 20px; padding-block: 44px; scroll-margin-top: 24px; }
.support h2 { font-size: 1.4rem; }
.support p { margin-top: 8px; color: var(--muted); font-size: .875rem; }
.support .text-link { overflow-wrap: anywhere; font-size: .875rem; width: fit-content; }
.site-footer { padding-block: 24px 28px; border-top: 1px solid var(--line); color: var(--muted); font-size: .8125rem; display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px 28px; }
.site-footer p { margin: 0; }
.site-footer p span { padding-inline: 6px; color: var(--gold); }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 0 24px; }
.site-footer a { min-height: 44px; display: inline-flex; align-items: center; }
.site-footer a[aria-current="page"] { color: var(--gold); }
.skip-link { position: absolute; top: 12px; left: 20px; transform: translateY(-200%); z-index: 10; background: var(--text); color: var(--navy); padding: 10px 18px; }
.skip-link:focus { transform: none; color: var(--navy); }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.legal-shell { min-height: 100svh; display: flex; flex-direction: column; }
.legal-main { flex: 1; padding-block: 64px 96px; }
.legal-content { max-width: 68ch; margin-inline: auto; }
.legal-content h1 { font-size: clamp(2rem, 5vw, 3.25rem); line-height: 1.2; margin: 0 0 24px; }
.legal-content h2 { font-size: 1.5rem; margin: 2em 0 .75em; }
.legal-content h3 { font-size: 1.125rem; margin: 1.75em 0 .5em; }
.legal-content p, .legal-content li { color: var(--muted); }
.legal-content .last-updated { font-size: .8125rem; margin: 0 0 36px; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.legal-return { margin-top: 32px; }
.legal-return a { display: inline-flex; align-items: center; min-height: 44px; color: var(--gold); }
.terms-heading { margin-bottom: 28px; }
.terms-heading h1 { font-size: clamp(2rem,5vw,3.25rem); line-height: 1.2; margin: 0 0 18px; }
.terms-heading .last-updated { color: var(--muted); font-size: .875rem; }
.terms-layout { display: grid; gap: 32px; align-items: start; }
.terms-content { min-width: 0; width: 100%; line-height: 1.85; }
.terms-content p + p { margin-top: 1.2em; }
.terms-content section { scroll-margin-top: 24px; }
.terms-content section h2 { padding-top: 1.8em; margin: 0 0 1em; }
.terms-content section:focus { outline-offset: 8px; }
.terms-content ul { padding-left: 1.4em; margin-block: 1.2em; }
.terms-content li + li { margin-top: .7em; }
.terms-content a { color: var(--gold); overflow-wrap: anywhere; }
.toc-desktop { display: none; }
.toc-mobile { border-block: 1px solid var(--line); }
.toc-mobile summary { cursor: pointer; min-height: 48px; padding: 12px 4px; color: var(--gold); }
.terms-toc ol { padding-left: 1.5em; margin: 8px 0 16px; font-size: .875rem; color: var(--muted); }
.terms-toc li { padding-left: .2em; }
.terms-toc a { display: flex; align-items: center; min-height: 44px; line-height: 1.5; text-decoration: none; padding: 7px 4px; }
.toc-title { font-size: .9375rem; color: var(--gold); font-weight: 550; }
@media (min-width: 1000px) {
  .terms-layout { grid-template-columns: 220px minmax(0,1fr); gap: 64px; }
  .terms-heading { margin-left: 284px; }
  .terms-toc { position: sticky; top: 24px; }
  .toc-desktop { display: block; max-height: calc(100svh - 48px); overflow-y: auto; scrollbar-width: thin; padding: 6px; }
  .toc-mobile { display: none; }
  .terms-content { margin-inline: 0; }
}
@media (min-width: 680px) {
  .page-shell { width: min(100% - 72px,1120px); }
  .hero { grid-template-columns: 1fr 1fr; gap: 36px; align-items: center; padding-block: 70px; }
  .intro { font-size: 1.125rem; }
  .rule { grid-template-columns: 1fr 1fr; align-items: center; gap: 28px; }
  .mode-list > div { grid-template-columns: 190px 1fr; gap: 24px; }
  .world { grid-template-columns: 1.5fr 1fr; align-items: center; gap: 36px; padding-block: 20px 40px; }
  .world-earth { grid-template-columns: 1fr 1.5fr; }
  .world-earth .world-image { grid-column: 2; grid-row: 1; }
  .world-earth .world-copy { grid-column: 1; grid-row: 1; }
  .section-heading { display: flex; justify-content: space-between; gap: 30px; align-items: end; }
}
@media (min-width: 1000px) {
  .site-header { min-height: 100px; flex-wrap: nowrap; }
  .js .menu-toggle { display: none; }
  .primary-navigation, .js .primary-navigation, .js .primary-navigation.is-open { display: flex; width: auto; padding: 0; justify-content: flex-end; gap: 22px; }
  .hero { padding-block: 82px 94px; gap: 90px; }
  .demo { max-width: 366px; justify-self: end; }
  .section { padding-block: 76px; }
  .rules, .modes, .faq { display: grid; grid-template-columns: .9fr 1.5fr; gap: 80px; }
  .rule-list, .mode-list, .faq-list { margin: 0; }
  .rule { grid-template-columns: 1.15fr 1fr; gap: 26px; }
  .rule:first-child { padding-top: 0; }
  .support { grid-template-columns: 1fr auto; align-items: center; padding-block: 44px 48px; }
  .legal-main { padding-block: 96px 120px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}