:root {
  --ink: #181a27;
  --ink-soft: #343746;
  --paper: #f6f2e9;
  --paper-deep: #ece5d8;
  --surface: #fffdf8;
  --line: rgba(24, 26, 39, 0.14);
  --line-strong: rgba(24, 26, 39, 0.25);
  --accent: #ec5f4f;
  --accent-dark: #c63f33;
  --accent-soft: #f7c7be;
  --gold: #d9a75e;
  --gold-light: #f1d69f;
  --board: #d8a861;
  --board-dark: #8d5b2f;
  --white-stone: #f9f7f1;
  --muted: #6e706f;
  --success: #267a5d;
  --shadow-sm: 0 8px 28px rgba(24, 26, 39, 0.08);
  --shadow-md: 0 22px 70px rgba(24, 26, 39, 0.15);
  --shadow-board: 0 28px 70px rgba(39, 25, 14, 0.25);
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 32px;
  --shell: 1180px;
  --header-height: 76px;
  font-synthesis: none;
  text-rendering: optimizeLegibility;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--paper); }
body {
  margin: 0;
  min-width: 320px;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, Pretendard, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans KR", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
body::selection { background: var(--accent-soft); color: var(--ink); }
img, svg, canvas { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, input, select { font: inherit; }
button, summary, select, label { -webkit-tap-highlight-color: transparent; }
button { color: inherit; }
p, h1, h2, h3, h4 { margin-top: 0; }
p:last-child { margin-bottom: 0; }

.shell { width: min(calc(100% - 40px), var(--shell)); margin-inline: auto; }
.narrow { max-width: 820px; }
.section { padding: 112px 0; }
.compact-section { padding: 88px 0; }
.surface-section { background: var(--surface); border-block: 1px solid var(--line); }
.eyebrow {
  margin: 0 0 16px;
  color: var(--accent-dark);
  font-size: 0.74rem;
  font-weight: 850;
  letter-spacing: 0.16em;
  line-height: 1.2;
  text-transform: uppercase;
}
.section-heading { max-width: 740px; margin-bottom: 48px; }
.section-heading h2,
.content-section h2,
.final-cta h2,
.article-cta h2,
.course-next h2 {
  margin-bottom: 16px;
  font-size: clamp(2rem, 4vw, 3.45rem);
  line-height: 1.08;
  letter-spacing: -0.045em;
}
.section-heading > p:not(.eyebrow) { color: var(--muted); font-size: 1.05rem; }
.section-heading.centered { margin-inline: auto; text-align: center; }
.split-heading { max-width: none; display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(300px, 0.7fr); gap: 80px; align-items: end; }
.split-heading > p { margin-bottom: 8px; }

.skip-link {
  position: fixed;
  z-index: 9999;
  top: 12px;
  left: 12px;
  transform: translateY(-150%);
  padding: 10px 14px;
  border-radius: 8px;
  background: var(--ink);
  color: #fff;
  font-weight: 750;
}
.skip-link:focus { transform: translateY(0); }

/* Brand and global navigation */
.site-header {
  position: sticky;
  z-index: 100;
  top: 0;
  height: var(--header-height);
  border-bottom: 1px solid rgba(24, 26, 39, 0.1);
  background: color-mix(in srgb, var(--paper) 90%, transparent);
  backdrop-filter: blur(18px) saturate(130%);
}
.header-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 11px; min-width: max-content; }
.brand-mark { position: relative; display: grid; grid-template-columns: repeat(2, 8px); grid-template-rows: repeat(2, 8px); gap: 3px; width: 19px; height: 19px; }
.brand-mark > span { border-radius: 50%; background: var(--ink); }
.brand-mark > span:nth-child(2), .brand-mark > span:nth-child(3) { background: transparent; border: 1.5px solid var(--ink); }
.brand-mark > i { position: absolute; width: 5px; height: 5px; border-radius: 50%; top: 7px; left: 7px; background: var(--accent); box-shadow: 0 0 0 3px var(--paper); }
.brand-copy { display: flex; flex-direction: column; line-height: 1; }
.brand-copy strong { font-size: 1rem; letter-spacing: 0.13em; }
.brand-copy small { margin-top: 5px; color: var(--muted); font-size: 0.64rem; letter-spacing: -0.02em; }
.desktop-nav { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.desktop-nav > a,
.nav-popover > summary {
  display: flex;
  align-items: center;
  gap: 4px;
  min-height: 42px;
  padding: 0 14px;
  border-radius: 999px;
  color: var(--ink-soft);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 720;
  list-style: none;
}
.desktop-nav > a:hover,
.desktop-nav > a[aria-current="page"],
.nav-popover[data-active="true"] > summary,
.nav-popover > summary:hover { background: rgba(24,26,39,.065); color: var(--ink); }
summary::-webkit-details-marker { display: none; }
.nav-popover, .language-menu, .mobile-menu { position: relative; }
.nav-popover-panel,
.language-panel {
  position: absolute;
  z-index: 30;
  top: calc(100% + 10px);
  right: 0;
  min-width: 190px;
  padding: 8px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--surface);
  box-shadow: var(--shadow-md);
}
.nav-popover-panel { left: 0; right: auto; }
.nav-popover-panel a,
.language-panel a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 42px;
  padding: 0 12px;
  border-radius: 9px;
  font-size: .88rem;
  font-weight: 700;
}
.nav-popover-panel a:hover,
.nav-popover-panel a[aria-current="page"],
.language-panel a:hover,
.language-panel a[aria-current="true"] { background: var(--paper-deep); }
.header-actions { display: flex; align-items: center; gap: 10px; }
.language-menu > summary {
  display: flex;
  align-items: center;
  gap: 4px;
  min-height: 40px;
  padding: 0 10px;
  border-radius: 999px;
  cursor: pointer;
  font-size: .78rem;
  font-weight: 820;
  list-style: none;
}
.language-menu > summary:hover { background: rgba(24,26,39,.06); }
.mobile-menu { display: none; }

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 52px;
  padding: 0 23px;
  border: 1px solid transparent;
  border-radius: 999px;
  cursor: pointer;
  font-size: .92rem;
  font-weight: 800;
  line-height: 1.1;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}
.button svg, .text-link svg, .game-button svg, .privacy-note svg, .check-list svg, .article-meta svg, .path-footer svg, .keyboard-note svg, .drill-grid svg { fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--accent); color: #fff; box-shadow: 0 12px 28px rgba(198,63,51,.24); }
.button-primary:hover { background: var(--accent-dark); }
.button-dark { background: var(--ink); color: #fff; }
.button-light { background: #fff; color: var(--ink); box-shadow: 0 14px 35px rgba(0,0,0,.16); }
.button-ghost { border-color: var(--line-strong); background: transparent; color: var(--ink); }
.button-small { min-height: 42px; padding-inline: 16px; font-size: .82rem; }
.text-link { display: inline-flex; align-items: center; gap: 8px; color: var(--accent-dark); font-weight: 820; }
.text-link:hover { gap: 12px; }

/* Hero */
.hero-section { position: relative; overflow: hidden; padding: 86px 0 32px; background: var(--paper); }
.hero-glow { position: absolute; top: -280px; right: -180px; width: 720px; height: 720px; border-radius: 50%; background: radial-gradient(circle, rgba(236,95,79,.19), rgba(236,95,79,0) 67%); pointer-events: none; }
.hero-grid { position: relative; display: grid; grid-template-columns: minmax(0, .93fr) minmax(440px, .77fr); align-items: center; gap: 86px; }
.hero-copy h1 { max-width: 710px; margin-bottom: 26px; font-size: clamp(3.5rem, 7.2vw, 6.8rem); line-height: .94; letter-spacing: -.07em; }
.hero-copy h1 span, .hero-copy h1 em { display: block; }
.hero-copy h1 em { color: var(--accent); font-style: normal; }
.hero-intro { max-width: 650px; margin-bottom: 34px; color: var(--ink-soft); font-size: clamp(1rem, 1.5vw, 1.17rem); line-height: 1.75; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.hero-stats { display: flex; gap: 34px; margin-top: 48px; padding-top: 26px; border-top: 1px solid var(--line); }
.hero-stats > div { display: flex; flex-direction: column; }
.hero-stats strong { font-size: 1.15rem; letter-spacing: -.02em; }
.hero-stats span { color: var(--muted); font-size: .74rem; }
.hero-game-card { position: relative; padding: 16px; border: 1px solid rgba(255,255,255,.1); border-radius: 30px; background: var(--ink); color: #fff; box-shadow: var(--shadow-md); transform: rotate(1.1deg); }
.hero-game-card::before { content: ""; position: absolute; inset: 12px -16px -18px 16px; z-index: -1; border-radius: 30px; border: 1px solid var(--line-strong); background: var(--gold-light); transform: rotate(-3deg); }
.hero-card-head, .hero-card-foot { display: flex; align-items: center; min-height: 38px; padding: 0 7px; font-size: .72rem; }
.hero-card-head { gap: 8px; color: rgba(255,255,255,.7); }
.hero-card-head b { margin-left: auto; font-size: .62rem; letter-spacing: .12em; }
.status-dot { width: 7px; height: 7px; border-radius: 50%; background: #77d6a0; box-shadow: 0 0 0 5px rgba(119,214,160,.12); }
.hero-board-wrap { overflow: hidden; border-radius: 20px; background: var(--board); box-shadow: inset 0 0 0 1px rgba(0,0,0,.18); }
.hero-board-svg { width: 100%; }
.hero-board-svg .board-lines { fill: var(--board-dark); stroke: rgba(69,41,20,.54); stroke-width: 1; }
.hero-board-svg .stone-black circle:first-child { fill: #181818; filter: drop-shadow(0 2px 2px rgba(0,0,0,.25)); }
.hero-board-svg .stone-white circle:first-child { fill: #faf7ee; stroke: rgba(0,0,0,.15); filter: drop-shadow(0 2px 2px rgba(0,0,0,.2)); }
.hero-board-svg .last-dot { fill: var(--accent); }
.hero-board-svg .hint-pulse circle:first-child { fill: none; stroke: var(--accent); stroke-width: 2; animation: pulseRing 2s infinite; transform-origin: center; }
.hero-board-svg .hint-pulse circle:last-child { fill: var(--accent); }
.hero-card-foot { justify-content: space-between; color: rgba(255,255,255,.78); }
.thinking-bars { display: flex; align-items: end; gap: 3px; height: 13px; }
.thinking-bars i { width: 3px; height: 5px; border-radius: 5px; background: var(--accent); animation: thinkingBars .9s infinite alternate; }
.thinking-bars i:nth-child(2) { height: 9px; animation-delay: .14s; }
.thinking-bars i:nth-child(3) { height: 12px; animation-delay: .28s; }
.trust-row { display: flex; justify-content: flex-end; gap: 24px; margin-top: 48px; color: var(--muted); }
.trust-row span { display: inline-flex; align-items: center; gap: 7px; font-size: .75rem; font-weight: 700; }
.trust-row svg { fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }

/* Cards and learning path */
.feature-section { background: var(--surface); border-block: 1px solid var(--line); }
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.feature-card { position: relative; min-height: 330px; padding: 36px 30px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--paper); overflow: hidden; }
.feature-card:nth-child(2) { background: var(--ink); color: #fff; }
.feature-card:nth-child(2) p { color: rgba(255,255,255,.67); }
.feature-card:nth-child(3) { background: var(--gold-light); }
.card-index { position: absolute; top: 18px; right: 20px; color: var(--muted); font-size: .7rem; font-weight: 800; letter-spacing: .12em; }
.feature-icon { display: grid; place-items: center; width: 52px; height: 52px; margin-bottom: 70px; border-radius: 16px; background: var(--surface); color: var(--accent-dark); box-shadow: var(--shadow-sm); }
.feature-icon svg { fill: none; stroke: currentColor; stroke-width: 1.55; stroke-linecap: round; stroke-linejoin: round; }
.feature-card h3 { margin-bottom: 12px; font-size: 1.36rem; letter-spacing: -.03em; }
.feature-card p { color: var(--muted); font-size: .92rem; }
.path-section { position: relative; }
.path-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.path-card { display: flex; flex-direction: column; min-height: 360px; padding: 30px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--surface); transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease; }
.path-card:hover { transform: translateY(-7px); border-color: var(--accent); box-shadow: var(--shadow-md); }
.path-number { margin-bottom: 34px; color: rgba(24,26,39,.26); font-size: 2.8rem; font-weight: 900; line-height: 1; letter-spacing: -.06em; }
.level-pill { align-self: flex-start; margin-bottom: 14px; padding: 5px 10px; border-radius: 999px; background: var(--paper-deep); color: var(--accent-dark); font-size: .7rem; font-weight: 850; }
.path-card h3 { margin-bottom: 12px; font-size: 1.35rem; line-height: 1.28; letter-spacing: -.035em; }
.path-card p { color: var(--muted); font-size: .9rem; }
.path-footer { display: flex; align-items: center; justify-content: space-between; margin-top: auto; padding-top: 18px; border-top: 1px solid var(--line); font-size: .77rem; font-weight: 750; }
.path-footer > span { display: flex; align-items: center; gap: 6px; color: var(--muted); }
.rules-teaser { padding: 0 0 112px; }
.rules-teaser-grid { display: grid; grid-template-columns: .8fr 1fr; gap: 80px; align-items: center; padding: 72px; border-radius: var(--radius-lg); background: var(--ink); color: #fff; overflow: hidden; }
.rules-visual { position: relative; display: grid; place-items: center; min-height: 350px; border-radius: 24px; background: radial-gradient(circle at 50% 50%, rgba(236,95,79,.28), transparent 62%), rgba(255,255,255,.035); }
.rule-five { display: flex; gap: 13px; transform: rotate(-20deg); }
.rule-five i { width: 38px; height: 38px; border-radius: 50%; background: #111; box-shadow: 0 8px 16px rgba(0,0,0,.4); animation: stoneRise 2.4s calc(var(--i) * .12s) infinite alternate ease-in-out; }
.rules-visual > span { position: absolute; right: 28px; bottom: 12px; color: rgba(255,255,255,.07); font-size: 9rem; font-weight: 950; line-height: 1; }
.rules-teaser-copy > p:not(.eyebrow) { color: rgba(255,255,255,.68); }
.check-list { display: grid; gap: 12px; padding: 0; margin: 28px 0; list-style: none; }
.check-list li { display: flex; gap: 10px; align-items: flex-start; }
.check-list svg { flex: 0 0 auto; margin-top: 4px; color: var(--accent); }
.rules-teaser .text-link { color: var(--accent-soft); }

/* FAQ */
.faq-shell { display: grid; grid-template-columns: .55fr 1fr; gap: 90px; align-items: start; }
.faq-list { border-top: 1px solid var(--line-strong); }
.faq-list details { border-bottom: 1px solid var(--line-strong); }
.faq-list summary { display: flex; align-items: center; justify-content: space-between; gap: 20px; min-height: 78px; cursor: pointer; font-weight: 800; list-style: none; }
.faq-list summary i { display: grid; place-items: center; flex: 0 0 auto; width: 28px; height: 28px; border-radius: 50%; border: 1px solid var(--line-strong); font-style: normal; transition: transform .2s; }
.faq-list details[open] summary i { transform: rotate(45deg); background: var(--ink); color: #fff; }
.faq-answer { padding: 0 44px 24px 0; color: var(--muted); font-size: .94rem; }
.final-cta, .article-cta, .course-next { background: var(--accent); color: #fff; }
.final-cta-inner, .article-cta-inner, .course-next-inner { display: flex; align-items: center; justify-content: space-between; gap: 40px; min-height: 250px; padding-block: 58px; }
.final-cta .eyebrow, .article-cta .eyebrow, .course-next .eyebrow { color: rgba(255,255,255,.7); }
.final-cta h2, .article-cta h2, .course-next h2 { margin: 0; }

/* Footer */
.site-footer { padding: 76px 0 24px; background: var(--ink); color: #fff; }
.footer-grid { display: grid; grid-template-columns: 1.7fr repeat(3, .6fr); gap: 60px; padding-bottom: 64px; }
.brand-footer .brand-mark > span { background: #fff; }
.brand-footer .brand-mark > span:nth-child(2), .brand-footer .brand-mark > span:nth-child(3) { background: transparent; border-color: #fff; }
.brand-footer .brand-mark > i { box-shadow: 0 0 0 3px var(--ink); }
.brand-footer .brand-copy small { color: rgba(255,255,255,.55); }
.footer-brand p { max-width: 420px; margin: 22px 0; color: rgba(255,255,255,.58); font-size: .88rem; }
.privacy-note { display: flex; gap: 8px; align-items: flex-start; max-width: 440px; color: rgba(255,255,255,.5); font-size: .73rem; }
.footer-column { display: flex; flex-direction: column; gap: 10px; }
.footer-column strong { margin-bottom: 8px; color: rgba(255,255,255,.9); font-size: .75rem; letter-spacing: .12em; text-transform: uppercase; }
.footer-column a { color: rgba(255,255,255,.57); font-size: .82rem; }
.footer-column a:hover { color: #fff; }
.footer-bottom { display: flex; justify-content: space-between; gap: 20px; padding-top: 22px; border-top: 1px solid rgba(255,255,255,.11); color: rgba(255,255,255,.42); font-size: .68rem; }

/* Breadcrumbs and article hero */
.breadcrumbs { margin-bottom: 34px; }
.breadcrumbs ol { display: flex; flex-wrap: wrap; gap: 8px; padding: 0; margin: 0; color: var(--muted); font-size: .72rem; list-style: none; }
.breadcrumbs li + li::before { content: "/"; margin-right: 8px; color: rgba(24,26,39,.28); }
.breadcrumbs a:hover { color: var(--accent-dark); }
.article-hero { padding: 72px 0 86px; border-bottom: 1px solid var(--line); background: var(--paper); }
.article-hero-grid { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(280px, .5fr); gap: 70px; align-items: end; }
.article-hero h1 { max-width: 900px; margin-bottom: 24px; font-size: clamp(3rem, 6vw, 5.8rem); line-height: .98; letter-spacing: -.065em; }
.article-intro { max-width: 760px; color: var(--ink-soft); font-size: 1.08rem; line-height: 1.8; }
.article-meta { display: flex; gap: 22px; margin-top: 30px; color: var(--muted); font-size: .72rem; }
.article-meta span { display: flex; align-items: center; gap: 6px; }
.article-hero-mark { position: relative; display: flex; flex-direction: column; align-items: flex-end; justify-content: flex-end; min-height: 240px; padding: 30px; border-radius: var(--radius-md); background: var(--ink); color: #fff; overflow: hidden; }
.article-hero-mark::before { content: ""; position: absolute; inset: 20px; border: 1px solid rgba(255,255,255,.12); border-radius: 14px; }
.article-hero-mark span { font-size: 9rem; font-weight: 950; line-height: .75; letter-spacing: -.09em; }
.article-hero-mark small { margin-top: 18px; color: var(--accent-soft); font-weight: 850; letter-spacing: .16em; }
.content-section { padding: 100px 0; }
.content-section h2 { max-width: 850px; }
.step-list { margin-top: 42px; border-top: 1px solid var(--line-strong); }
.step-item { display: grid; grid-template-columns: 90px 1fr; gap: 24px; padding: 34px 0; border-bottom: 1px solid var(--line-strong); }
.step-item > span { color: var(--accent); font-size: 1.05rem; font-weight: 900; }
.step-item h3 { margin-bottom: 7px; font-size: 1.25rem; }
.step-item p { color: var(--muted); }
.responsive-table { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--paper); }
table { width: 100%; min-width: 820px; border-collapse: collapse; }
th, td { padding: 20px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; font-size: .86rem; }
thead th { background: var(--ink); color: #fff; font-size: .7rem; letter-spacing: .08em; text-transform: uppercase; }
tbody th { color: var(--accent-dark); font-weight: 850; }
tbody tr:last-child th, tbody tr:last-child td { border-bottom: 0; }
.forbidden-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.forbidden-grid article { padding: 20px 20px 30px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--surface); }
.pattern-visual { margin-bottom: 24px; border-radius: 14px; background: var(--board); overflow: hidden; }
.pattern-svg { width: 100%; }
.mini-lines { fill: var(--board-dark); stroke: rgba(70,40,18,.52); stroke-width: 1; }
.mini-black { fill: #191919; filter: drop-shadow(0 2px 2px rgba(0,0,0,.28)); }
.mini-white { fill: #faf8f1; stroke: rgba(0,0,0,.13); }
.mini-hint circle { fill: rgba(236,95,79,.13); stroke: var(--accent); stroke-width: 2; }
.mini-hint path { fill: none; stroke: var(--accent-dark); stroke-width: 2; }
.mini-forbidden circle { fill: rgba(236,95,79,.9); }
.mini-forbidden path { fill: none; stroke: white; stroke-width: 2.5; stroke-linecap: round; }
.forbidden-code { display: inline-flex; margin-bottom: 14px; padding: 5px 9px; border-radius: 7px; background: var(--accent-soft); color: var(--accent-dark); font-size: .72rem; font-weight: 900; }
.forbidden-grid h3 { margin-bottom: 10px; font-size: 1.2rem; }
.forbidden-grid p { color: var(--muted); font-size: .88rem; }
.dark-content { background: var(--ink); color: #fff; }
.dark-content .eyebrow { color: var(--accent-soft); }
.dark-content-grid { display: grid; grid-template-columns: .8fr 1fr; gap: 90px; align-items: start; }
.dark-content-grid ol { counter-reset: order; display: grid; gap: 16px; padding: 0; margin: 0; list-style: none; }
.dark-content-grid li { counter-increment: order; display: grid; grid-template-columns: 48px 1fr; gap: 16px; align-items: center; padding: 18px; border: 1px solid rgba(255,255,255,.13); border-radius: 14px; color: rgba(255,255,255,.72); }
.dark-content-grid li::before { content: counter(order, decimal-leading-zero); display: grid; place-items: center; width: 42px; height: 42px; border-radius: 50%; background: var(--accent); color: #fff; font-size: .72rem; font-weight: 900; }
.glossary-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.glossary-grid > div { padding: 26px; border: 1px solid var(--line); border-radius: var(--radius-sm); background: var(--surface); }
.glossary-grid dt { margin-bottom: 8px; color: var(--accent-dark); font-weight: 900; }
.glossary-grid dd { margin: 0; color: var(--muted); font-size: .88rem; }

/* Strategy */
.strategy-aside { position: relative; border-radius: var(--radius-md); background: var(--board); overflow: hidden; box-shadow: var(--shadow-md); }
.strategy-aside > span { position: absolute; right: 20px; bottom: 10px; color: rgba(24,26,39,.18); font-size: 4rem; font-weight: 950; letter-spacing: -.08em; }
.priority-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.priority-grid article { min-height: 280px; padding: 26px; border-radius: var(--radius-md); background: var(--surface); border: 1px solid var(--line); }
.priority-grid article > span { display: grid; place-items: center; width: 40px; height: 40px; margin-bottom: 55px; border-radius: 50%; background: var(--ink); color: #fff; font-weight: 900; }
.priority-grid h3 { margin-bottom: 10px; font-size: 1.12rem; line-height: 1.3; }
.priority-grid p { color: var(--muted); font-size: .85rem; }
.pattern-ranking { display: grid; gap: 12px; }
.pattern-ranking article { display: grid; grid-template-columns: 74px 170px 1fr; gap: 28px; align-items: center; padding: 18px 24px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--paper); }
.rank-mark { display: grid; place-items: center; width: 54px; height: 54px; border-radius: 17px; background: var(--accent); color: #fff; font-size: 1.35rem; font-weight: 950; }
.rank-board { overflow: hidden; border-radius: 12px; background: var(--board); }
.pattern-ranking article > div:last-child > span { color: var(--accent-dark); font-size: .72rem; font-weight: 850; }
.pattern-ranking h3 { margin: 2px 0 6px; font-size: 1.25rem; }
.pattern-ranking p { color: var(--muted); font-size: .88rem; }
.strategy-two-col { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.strategy-copy { padding: 44px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--surface); }
.strategy-copy.accent-copy { background: var(--gold-light); }
.strategy-copy h2 { font-size: clamp(1.8rem,3vw,2.6rem); }
.strategy-copy > p:not(.eyebrow) { color: var(--muted); }
.dot-list { display: grid; gap: 12px; padding-left: 20px; margin-top: 26px; }
.dot-list li { padding-left: 4px; }
.strategy-copy ol { counter-reset: defense; display: grid; gap: 12px; padding: 0; margin: 26px 0 0; list-style: none; }
.strategy-copy ol li { counter-increment: defense; display: grid; grid-template-columns: 30px 1fr; gap: 10px; }
.strategy-copy ol li::before { content: counter(defense); display: grid; place-items: center; width: 25px; height: 25px; border-radius: 50%; background: var(--ink); color: #fff; font-size: .68rem; font-weight: 850; }
.calculation-grid { display: grid; grid-template-columns: 1fr .9fr; gap: 80px; align-items: center; }
.calculation-grid > div:first-child > p:last-child { color: rgba(255,255,255,.65); }
.formula-card { padding: 34px; border: 1px solid rgba(255,255,255,.15); border-radius: var(--radius-md); background: rgba(255,255,255,.04); }
.formula-card > span { display: block; margin-bottom: 28px; color: var(--accent-soft); font-weight: 850; }
.formula-card > div { display: flex; align-items: center; gap: 12px; }
.formula-card i { width: 42px; height: 42px; border-radius: 50%; background: #0e0f15; box-shadow: inset -5px -5px 9px rgba(255,255,255,.07); }
.formula-card i:nth-of-type(2) { background: #fff; box-shadow: inset -5px -5px 9px rgba(0,0,0,.12); }
.formula-card i:nth-of-type(3) { background: var(--accent); }
.formula-card svg { fill: none; stroke: rgba(255,255,255,.5); stroke-width: 1.7; }
.mistake-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.mistake-grid article { position: relative; padding: 32px 32px 32px 86px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--surface); }
.mistake-grid article > span { position: absolute; top: 30px; left: 28px; color: var(--accent); font-size: .78rem; font-weight: 900; }
.mistake-grid h3 { margin-bottom: 8px; font-size: 1.15rem; }
.mistake-grid p { color: var(--muted); font-size: .87rem; }
.drill-section { padding-top: 0; }
.drill-grid { display: grid; grid-template-columns: .8fr 1fr auto; gap: 40px; align-items: center; padding: 46px; border-radius: var(--radius-lg); background: var(--gold-light); }
.drill-grid ol { display: grid; gap: 9px; padding: 0; margin: 0; list-style: none; }
.drill-grid li { display: flex; align-items: center; gap: 9px; font-size: .86rem; font-weight: 700; }
.drill-grid li svg { color: var(--accent-dark); }

/* Play page and game */
.play-hero { padding: 54px 0 38px; }
.play-hero h1 { max-width: 900px; margin-bottom: 16px; font-size: clamp(2.8rem,5.7vw,5.2rem); line-height: 1; letter-spacing: -.06em; }
.play-hero .shell > p:last-child { max-width: 800px; color: var(--muted); }
.game-shell { margin-bottom: 70px; }
.game-stage { position: relative; padding: 18px; border: 1px solid rgba(255,255,255,.08); border-radius: 28px; background: var(--ink); color: #fff; box-shadow: var(--shadow-md); }
.game-topbar { display: flex; align-items: center; justify-content: space-between; min-height: 58px; padding: 0 10px 12px; }
.game-status { display: flex; align-items: center; gap: 12px; }
.game-status small, .game-metrics small { display: block; color: rgba(255,255,255,.5); font-size: .64rem; letter-spacing: .08em; text-transform: uppercase; }
.game-status strong { display: block; margin-top: 2px; font-size: .95rem; }
.turn-stone { width: 27px; height: 27px; border-radius: 50%; box-shadow: inset -4px -4px 7px rgba(255,255,255,.08), 0 4px 10px rgba(0,0,0,.35); }
.turn-black { background: #090a0d; border: 1px solid rgba(255,255,255,.15); }
.turn-white { background: #f8f6ee; border: 1px solid rgba(0,0,0,.15); }
.game-metrics { display: flex; gap: 18px; }
.game-metrics > span { min-width: 54px; }
.game-metrics strong { font-size: .86rem; font-variant-numeric: tabular-nums; }
.game-main-grid { display: grid; grid-template-columns: minmax(0, 1fr) 330px; gap: 16px; }
.board-panel { min-width: 0; }
.board-frame { position: relative; display: grid; place-items: center; width: 100%; border-radius: 20px; background: var(--board); overflow: hidden; box-shadow: var(--shadow-board), inset 0 0 0 1px rgba(0,0,0,.18); touch-action: manipulation; }
.gomoku-board { width: 100%; height: auto; aspect-ratio: 1; outline: none; cursor: crosshair; touch-action: none; }
.gomoku-board:focus-visible { box-shadow: inset 0 0 0 4px var(--accent-soft); }
.ai-overlay { position: absolute; inset: 0; display: grid; place-content: center; justify-items: center; gap: 14px; background: rgba(24,26,39,.22); backdrop-filter: blur(1.5px); pointer-events: none; }
.ai-overlay[hidden] { display: none; }
.ai-overlay strong { padding: 7px 12px; border-radius: 999px; background: rgba(24,26,39,.86); font-size: .76rem; }
.thinking-orbit { position: relative; width: 48px; height: 48px; border: 2px solid rgba(255,255,255,.28); border-top-color: #fff; border-radius: 50%; animation: spin 1s linear infinite; }
.thinking-orbit i { position: absolute; top: 4px; left: 50%; width: 10px; height: 10px; border-radius: 50%; background: var(--accent); transform: translateX(-50%); }
.keyboard-note { display: flex; align-items: center; justify-content: center; gap: 7px; margin: 12px 0 0; color: rgba(255,255,255,.44); font-size: .68rem; }
.game-action-row { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 8px; margin-top: 12px; }
.game-button { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 48px; padding: 0 14px; border: 1px solid rgba(255,255,255,.14); border-radius: 13px; background: rgba(255,255,255,.06); color: #fff; cursor: pointer; font-size: .78rem; font-weight: 800; }
.game-button:hover { background: rgba(255,255,255,.11); }
.game-button.primary { border-color: var(--accent); background: var(--accent); }
.game-button:disabled { opacity: .4; cursor: not-allowed; }
.game-sidebar { display: flex; flex-direction: column; gap: 10px; }
.control-card { padding: 18px; border: 1px solid rgba(255,255,255,.1); border-radius: 16px; background: rgba(255,255,255,.045); }
.control-card-title { display: flex; align-items: center; gap: 9px; margin-bottom: 16px; }
.control-card-title > span { display: grid; place-items: center; width: 30px; height: 30px; border-radius: 9px; background: rgba(255,255,255,.08); color: var(--accent-soft); }
.control-card-title svg, .install-card svg { fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.control-card-title h2 { margin: 0; font-size: .88rem; }
.control-card fieldset { padding: 0; margin: 0 0 14px; border: 0; }
.control-card legend { margin-bottom: 7px; color: rgba(255,255,255,.53); font-size: .66rem; font-weight: 750; }
.segmented { display: grid; gap: 4px; padding: 4px; border-radius: 10px; background: rgba(0,0,0,.22); }
.segmented.two { grid-template-columns: repeat(2, 1fr); }
.segmented.three { grid-template-columns: repeat(3, 1fr); }
.segmented label { position: relative; cursor: pointer; }
.segmented input { position: absolute; opacity: 0; pointer-events: none; }
.segmented span { display: flex; align-items: center; justify-content: center; gap: 5px; min-height: 34px; padding: 0 5px; border-radius: 7px; color: rgba(255,255,255,.57); font-size: .67rem; font-weight: 760; text-align: center; }
.segmented input:checked + span { background: rgba(255,255,255,.13); color: #fff; box-shadow: 0 3px 10px rgba(0,0,0,.18); }
.segmented input:focus-visible + span { outline: 2px solid var(--accent-soft); outline-offset: 1px; }
.tiny-stone { width: 12px; height: 12px; border-radius: 50%; }
.tiny-stone.black { background: #090a0d; border: 1px solid rgba(255,255,255,.25); }
.tiny-stone.white { background: #fff; }
.setting-description { margin: 7px 3px 0; color: rgba(255,255,255,.42); font-size: .61rem; line-height: 1.45; }
.control-card select { width: 100%; min-height: 40px; padding: 0 12px; border: 1px solid rgba(255,255,255,.13); border-radius: 9px; background: #2a2c38; color: #fff; font-size: .72rem; }
.toggle-row { display: grid; grid-template-columns: repeat(2,1fr); gap: 7px; }
.toggle-row label { display: flex; align-items: center; justify-content: space-between; min-height: 42px; padding: 0 10px; border-radius: 9px; background: rgba(0,0,0,.2); font-size: .64rem; font-weight: 700; }
.toggle-row label > span { display: flex; align-items: center; gap: 5px; color: rgba(255,255,255,.65); }
.toggle-row svg { fill: none; stroke: currentColor; stroke-width: 1.7; }
.switch { position: relative; appearance: none; width: 30px; height: 18px; margin: 0; border-radius: 999px; background: rgba(255,255,255,.18); cursor: pointer; transition: background .2s; }
.switch::after { content: ""; position: absolute; top: 3px; left: 3px; width: 12px; height: 12px; border-radius: 50%; background: #fff; transition: transform .2s; }
.switch:checked { background: var(--accent); }
.switch:checked::after { transform: translateX(12px); }
.record-card { margin-top: auto; }
.record-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 5px; }
.record-grid > div { display: flex; flex-direction: column; align-items: center; padding: 10px 3px; border-radius: 9px; background: rgba(0,0,0,.2); }
.record-grid strong { font-size: 1rem; }
.record-grid span { color: rgba(255,255,255,.43); font-size: .57rem; }
.text-button { display: block; margin: 10px auto 0; border: 0; background: transparent; color: rgba(255,255,255,.43); cursor: pointer; font-size: .62rem; text-decoration: underline; text-underline-offset: 3px; }
.install-card { display: flex; gap: 11px; padding: 14px; border-radius: 14px; background: var(--gold-light); color: var(--ink); }
.install-card > span { flex: 0 0 auto; }
.install-card strong { display: block; font-size: .72rem; }
.install-card p { margin: 3px 0 0; color: rgba(24,26,39,.65); font-size: .58rem; line-height: 1.35; }
.toast { position: fixed; z-index: 1000; left: 50%; bottom: calc(26px + env(safe-area-inset-bottom)); transform: translate(-50%, 12px); max-width: min(92vw, 440px); padding: 11px 16px; border-radius: 999px; background: rgba(24,26,39,.94); color: #fff; box-shadow: var(--shadow-md); font-size: .76rem; opacity: 0; transition: opacity .2s, transform .2s; }
.toast.is-visible { opacity: 1; transform: translate(-50%,0); }
.game-dialog { width: min(92vw, 430px); padding: 34px; border: 0; border-radius: 24px; background: var(--surface); color: var(--ink); text-align: center; box-shadow: var(--shadow-md); }
.game-dialog::backdrop { background: rgba(15,16,22,.7); backdrop-filter: blur(5px); }
.game-dialog h2 { margin-bottom: 8px; font-size: 2rem; letter-spacing: -.04em; }
.game-dialog > p:not(.eyebrow) { color: var(--muted); font-size: .88rem; }
.dialog-stones { display: flex; justify-content: center; gap: 6px; margin-bottom: 26px; }
.dialog-stones i { width: 22px; height: 22px; border-radius: 50%; background: #151515; box-shadow: 0 3px 6px rgba(0,0,0,.25); }
.dialog-stones i:nth-child(even) { background: #fff; border: 1px solid var(--line); }
.dialog-actions { display: flex; justify-content: center; gap: 8px; margin-top: 24px; }
.guide-grid, .ai-card-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 16px; }
.guide-grid article { padding: 28px; border-top: 2px solid var(--ink); background: var(--surface); }
.guide-grid article > span { color: var(--accent); font-size: .72rem; font-weight: 900; }
.guide-grid h3 { margin: 34px 0 9px; font-size: 1.15rem; }
.guide-grid p { color: var(--muted); font-size: .86rem; }
.ai-explainer { background: var(--surface); border-block: 1px solid var(--line); }
.ai-level-card { min-height: 310px; padding: 30px; border-radius: var(--radius-md); color: #fff; }
.ai-level-card.level-1 { background: #3b5e53; }
.ai-level-card.level-2 { background: var(--ink); }
.ai-level-card.level-3 { background: var(--accent-dark); }
.ai-level-card > div { display: flex; align-items: center; justify-content: space-between; }
.level-orb { display: grid; place-items: center; width: 46px; height: 46px; border: 1px solid rgba(255,255,255,.25); border-radius: 50%; font-weight: 900; }
.level-badge { padding: 5px 9px; border-radius: 999px; background: rgba(255,255,255,.12); font-size: .63rem; font-weight: 800; }
.ai-level-card h3 { margin: 80px 0 10px; font-size: 1.5rem; }
.ai-level-card p { color: rgba(255,255,255,.68); font-size: .85rem; }

/* Course pages */
.course-hero-card { display: flex; flex-direction: column; justify-content: flex-end; min-height: 240px; padding: 28px; border-radius: var(--radius-md); background: var(--gold-light); overflow: hidden; }
.course-hero-card > span { margin-bottom: auto; color: rgba(24,26,39,.18); font-size: 7rem; font-weight: 950; line-height: .8; letter-spacing: -.08em; }
.course-hero-card strong { font-size: 1.25rem; }
.course-hero-card small { display: flex; align-items: center; gap: 6px; margin-top: 8px; color: var(--muted); }
.course-hero-card svg { fill: none; stroke: currentColor; stroke-width: 1.7; }
.course-tabs { display: grid; grid-template-columns: repeat(3,1fr); margin-top: 28px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface); overflow: hidden; }
.course-tabs a { display: flex; align-items: center; justify-content: center; gap: 10px; min-height: 56px; border-right: 1px solid var(--line); color: var(--muted); font-size: .78rem; font-weight: 800; }
.course-tabs a:last-child { border-right: 0; }
.course-tabs a span { color: rgba(24,26,39,.3); }
.course-tabs a[aria-current="page"] { background: var(--ink); color: #fff; }
.course-tabs a[aria-current="page"] span { color: var(--accent-soft); }
.course-overview { padding-top: 70px; }
.course-overview-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 60px; align-items: start; }
.course-overview-grid .check-list { margin: 0; }
.course-progress-card { grid-column: 1 / -1; padding: 20px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface); }
.course-progress-card > div:first-child { display: flex; justify-content: space-between; margin-bottom: 10px; font-size: .74rem; font-weight: 800; }
.progress-track { height: 8px; border-radius: 999px; background: var(--paper-deep); overflow: hidden; }
.progress-track i { display: block; width: 0; height: 100%; border-radius: inherit; background: var(--accent); transition: width .4s ease; }
.lesson-list { display: grid; gap: 14px; }
.lesson-card { display: grid; grid-template-columns: 70px 1fr 110px; gap: 26px; align-items: start; padding: 30px; border: 1px solid var(--line); border-radius: var(--radius-md); background: var(--paper); transition: border-color .2s, opacity .2s; }
.lesson-card.is-complete { border-color: rgba(38,122,93,.45); }
.lesson-card.is-complete .lesson-content { opacity: .62; }
.lesson-number { display: flex; flex-direction: column; align-items: center; gap: 12px; }
.lesson-number span { color: var(--accent); font-size: .82rem; font-weight: 900; }
.lesson-number i { width: 1px; height: 80px; background: var(--line-strong); }
.lesson-content h3 { margin-bottom: 9px; font-size: 1.3rem; letter-spacing: -.03em; }
.lesson-content > p { color: var(--muted); font-size: .9rem; }
.lesson-tip { display: flex; gap: 9px; align-items: flex-start; margin-top: 18px; padding: 13px; border-radius: 10px; background: var(--gold-light); font-size: .76rem; }
.lesson-tip svg { flex: 0 0 auto; fill: none; stroke: currentColor; stroke-width: 1.7; }
.lesson-complete { min-height: 38px; padding: 0 12px; border: 1px solid var(--line-strong); border-radius: 999px; background: transparent; cursor: pointer; font-size: .67rem; font-weight: 800; }
.lesson-complete .checked { display: none; align-items: center; gap: 5px; }
.lesson-complete .checked svg { fill: none; stroke: currentColor; stroke-width: 2; }
.lesson-complete[aria-pressed="true"] { border-color: var(--success); background: var(--success); color: #fff; }
.lesson-complete[aria-pressed="true"] .unchecked { display: none; }
.lesson-complete[aria-pressed="true"] .checked { display: inline-flex; }
.challenge-section { background: var(--paper); }
.challenge-grid { display: grid; grid-template-columns: 90px 1fr 1fr auto; gap: 36px; align-items: center; padding: 44px; border-radius: var(--radius-lg); background: var(--ink); color: #fff; }
.challenge-mark { display: grid; place-items: center; width: 70px; height: 70px; border-radius: 22px; background: var(--accent); }
.challenge-mark svg { fill: none; stroke: currentColor; stroke-width: 1.7; }
.challenge-grid > div:nth-child(2) > p:last-child { color: rgba(255,255,255,.63); font-size: .86rem; }
.challenge-grid ul { display: grid; gap: 8px; padding: 0; margin: 0; list-style: none; }
.challenge-grid label { display: flex; align-items: center; gap: 9px; cursor: pointer; color: rgba(255,255,255,.7); font-size: .74rem; }
.challenge-grid input { position: absolute; opacity: 0; }
.challenge-grid label > span { display: grid; place-items: center; width: 21px; height: 21px; border: 1px solid rgba(255,255,255,.3); border-radius: 6px; }
.challenge-grid label svg { opacity: 0; fill: none; stroke: currentColor; stroke-width: 2; }
.challenge-grid input:checked + span { border-color: var(--accent); background: var(--accent); }
.challenge-grid input:checked + span svg { opacity: 1; }
.challenge-grid input:checked ~ b { color: rgba(255,255,255,.4); text-decoration: line-through; }
.challenge-grid b { font-weight: 650; }
.course-next-inner > div { max-width: 800px; }
.course-next-inner p:last-child { color: rgba(255,255,255,.72); }

/* Language hub / 404 */
.language-hub-page { min-height: 100vh; background: var(--ink); color: #fff; }
.language-hub { min-height: 100vh; display: grid; grid-template-columns: minmax(340px,.85fr) minmax(500px,1.15fr); }
.hub-board { display: grid; place-items: center; padding: 9vw; background: var(--board); overflow: hidden; }
.hub-board .hero-board-svg { width: min(620px,90%); transform: rotate(-4deg) scale(1.15); filter: drop-shadow(0 35px 50px rgba(0,0,0,.25)); }
.hub-content { display: flex; flex-direction: column; justify-content: center; padding: clamp(40px,8vw,120px); }
.hub-brand { margin-bottom: 70px; }
.hub-brand .brand-mark > span { background: #fff; }
.hub-brand .brand-mark > span:nth-child(2), .hub-brand .brand-mark > span:nth-child(3) { background: transparent; border-color: #fff; }
.hub-brand .brand-mark > i { box-shadow: 0 0 0 3px var(--ink); }
.hub-brand .brand-copy small { color: rgba(255,255,255,.5); }
.hub-content h1 { margin-bottom: 18px; font-size: clamp(3rem,6vw,6rem); line-height: .95; letter-spacing: -.065em; }
.hub-content > p:not(.eyebrow) { max-width: 620px; color: rgba(255,255,255,.6); }
.language-card-grid { display: grid; gap: 9px; margin-top: 42px; }
.language-card-grid a { display: grid; grid-template-columns: 46px 1fr 24px; gap: 16px; align-items: center; min-height: 78px; padding: 14px 18px; border: 1px solid rgba(255,255,255,.13); border-radius: 15px; background: rgba(255,255,255,.045); transition: background .2s, transform .2s; }
.language-card-grid a:hover { background: rgba(255,255,255,.1); transform: translateX(5px); }
.language-card-grid a > span { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 12px; background: var(--accent); font-size: .69rem; font-weight: 900; }
.language-card-grid strong, .language-card-grid small { display: block; }
.language-card-grid strong { font-size: .92rem; }
.language-card-grid small { color: rgba(255,255,255,.5); font-size: .68rem; }
.language-card-grid svg { fill: none; stroke: currentColor; stroke-width: 1.7; }
.hub-note { margin-top: 30px; color: rgba(255,255,255,.35); }
.not-found-page { min-height: 100vh; display: grid; place-items: center; background: var(--paper); }
.not-found { width: min(92vw,700px); text-align: center; }
.not-found-mark { display: flex; justify-content: center; align-items: center; gap: 18px; margin-bottom: 28px; font-size: 6rem; font-weight: 950; line-height: 1; }
.not-found-mark i { width: 62px; height: 62px; border-radius: 50%; background: #151515; box-shadow: inset -8px -8px 12px rgba(255,255,255,.08), 0 8px 18px rgba(0,0,0,.2); }
.not-found h1 { margin-bottom: 14px; font-size: clamp(2rem,5vw,4rem); letter-spacing: -.05em; }
.not-found p { color: var(--muted); }
.not-found > div:last-child { display: flex; flex-wrap: wrap; justify-content: center; gap: 9px; margin-top: 28px; }

@keyframes pulseRing { 0% { opacity: 1; transform: scale(.5); } 100% { opacity: 0; transform: scale(1.55); } }
@keyframes thinkingBars { to { height: 13px; opacity: .55; } }
@keyframes stoneRise { to { transform: translateY(-10px); } }
@keyframes spin { to { transform: rotate(360deg); } }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; }
}

@media (max-width: 1060px) {
  .desktop-nav { display: none; }
  .mobile-menu { display: block; }
  .mobile-menu > summary { display: grid; place-items: center; width: 42px; height: 42px; border-radius: 50%; background: var(--ink); color: #fff; cursor: pointer; list-style: none; }
  .mobile-menu svg { fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; }
  .mobile-menu-panel { position: fixed; z-index: 200; top: var(--header-height); right: 0; width: min(92vw,390px); max-height: calc(100vh - var(--header-height)); padding: 22px; border-left: 1px solid var(--line); border-bottom: 1px solid var(--line); border-radius: 0 0 0 24px; background: var(--surface); box-shadow: var(--shadow-md); overflow-y: auto; }
  .mobile-menu-top { padding-bottom: 18px; border-bottom: 1px solid var(--line); }
  .mobile-menu-panel nav { display: grid; padding: 12px 0; }
  .mobile-menu-panel nav a { min-height: 44px; padding: 0 12px; border-radius: 9px; font-weight: 800; }
  .mobile-menu-panel nav a[aria-current="page"] { background: var(--paper-deep); color: var(--accent-dark); }
  .mobile-nav-label { padding: 12px 12px 4px; color: var(--muted); font-size: .68rem; font-weight: 850; letter-spacing: .12em; text-transform: uppercase; }
  .mobile-language { display: grid; grid-template-columns: repeat(3,1fr); gap: 5px; padding-top: 14px; border-top: 1px solid var(--line); }
  .mobile-language a { display: flex; align-items: center; justify-content: center; min-height: 40px; border-radius: 8px; background: var(--paper); font-size: .7rem; font-weight: 800; }
  .mobile-language a svg { display: none; }
  .hero-grid { grid-template-columns: 1fr 440px; gap: 48px; }
  .game-main-grid { grid-template-columns: minmax(0,1fr) 290px; }
  .priority-grid { grid-template-columns: repeat(2,1fr); }
  .challenge-grid { grid-template-columns: 70px 1fr 1fr; }
  .challenge-grid > .button { grid-column: 2 / -1; justify-self: start; }
}

@media (max-width: 860px) {
  :root { --header-height: 68px; }
  .shell { width: min(calc(100% - 28px), var(--shell)); }
  .section { padding: 78px 0; }
  .compact-section { padding: 66px 0; }
  .desktop-play { display: none; }
  .hero-section { padding-top: 58px; }
  .hero-grid { grid-template-columns: 1fr; gap: 54px; }
  .hero-copy h1 { font-size: clamp(3.7rem,13vw,6rem); }
  .hero-game-card { width: min(100%,560px); margin-inline: auto; transform: rotate(.5deg); }
  .trust-row { justify-content: center; flex-wrap: wrap; }
  .feature-grid, .path-grid, .forbidden-grid, .guide-grid, .ai-card-grid { grid-template-columns: 1fr; }
  .feature-card { min-height: 270px; }
  .feature-icon { margin-bottom: 42px; }
  .split-heading { grid-template-columns: 1fr; gap: 10px; }
  .rules-teaser-grid { grid-template-columns: 1fr; padding: 45px; gap: 45px; }
  .rules-visual { min-height: 280px; }
  .faq-shell { grid-template-columns: 1fr; gap: 16px; }
  .article-hero-grid { grid-template-columns: 1fr; gap: 38px; }
  .article-hero-mark, .course-hero-card { min-height: 190px; }
  .article-hero-mark span { font-size: 7rem; }
  .dark-content-grid, .calculation-grid { grid-template-columns: 1fr; gap: 44px; }
  .glossary-grid, .strategy-two-col, .mistake-grid { grid-template-columns: 1fr; }
  .pattern-ranking article { grid-template-columns: 58px 130px 1fr; gap: 18px; }
  .drill-grid { grid-template-columns: 1fr; }
  .game-main-grid { grid-template-columns: 1fr; }
  .game-sidebar { display: grid; grid-template-columns: 1fr 1fr; }
  .control-card:first-child { grid-row: span 2; }
  .record-card { margin-top: 0; }
  .course-overview-grid { grid-template-columns: 1fr; gap: 28px; }
  .lesson-card { grid-template-columns: 55px 1fr; }
  .lesson-complete { grid-column: 2; justify-self: start; }
  .challenge-grid { grid-template-columns: 70px 1fr; }
  .challenge-grid ul, .challenge-grid > .button { grid-column: 2; }
  .language-hub { grid-template-columns: 1fr; }
  .hub-board { display: none; }
  .hub-content { min-height: 100vh; }
  .footer-grid { grid-template-columns: 1.5fr repeat(3, .7fr); gap: 30px; }
}

@media (max-width: 620px) {
  body { font-size: 15px; }
  .shell { width: min(calc(100% - 22px), var(--shell)); }
  .site-header .brand-copy small { display: none; }
  .language-menu { display: none; }
  .hero-section { padding-top: 42px; }
  .hero-copy h1 { font-size: clamp(3.35rem,17vw,5rem); }
  .hero-intro { font-size: .97rem; }
  .hero-actions { display: grid; grid-template-columns: 1fr; }
  .hero-actions .button { width: 100%; }
  .hero-stats { gap: 12px; }
  .hero-stats > div { flex: 1; }
  .hero-game-card { padding: 10px; border-radius: 21px; }
  .hero-game-card::before { inset: 8px -8px -10px 8px; border-radius: 21px; }
  .hero-board-wrap { border-radius: 14px; }
  .trust-row { gap: 10px 18px; }
  .trust-row span { font-size: .68rem; }
  .section-heading h2, .content-section h2, .final-cta h2, .article-cta h2, .course-next h2 { font-size: clamp(1.9rem,10vw,2.8rem); }
  .feature-card, .path-card { padding: 24px; }
  .rules-teaser { padding-bottom: 72px; }
  .rules-teaser-grid { width: 100%; border-radius: 0; padding: 52px 22px; }
  .rule-five i { width: 29px; height: 29px; }
  .rules-visual { min-height: 230px; }
  .faq-list summary { min-height: 70px; font-size: .9rem; }
  .final-cta-inner, .article-cta-inner, .course-next-inner { flex-direction: column; align-items: flex-start; min-height: 260px; }
  .footer-grid { grid-template-columns: repeat(2,1fr); }
  .footer-brand { grid-column: 1 / -1; }
  .footer-bottom { flex-direction: column; }
  .article-hero { padding: 42px 0 58px; }
  .article-hero h1 { font-size: clamp(2.7rem,14vw,4.2rem); }
  .article-intro { font-size: .98rem; }
  .article-meta { flex-wrap: wrap; }
  .article-hero-mark { min-height: 150px; }
  .article-hero-mark span { font-size: 5.8rem; }
  .content-section { padding: 72px 0; }
  .step-item { grid-template-columns: 52px 1fr; gap: 12px; padding: 25px 0; }
  .forbidden-grid article { padding: 14px 14px 24px; }
  .dark-content-grid li { grid-template-columns: 38px 1fr; padding: 13px; }
  .dark-content-grid li::before { width: 34px; height: 34px; }
  .glossary-grid > div, .strategy-copy { padding: 24px; }
  .priority-grid { grid-template-columns: 1fr; }
  .priority-grid article { min-height: 235px; }
  .priority-grid article > span { margin-bottom: 40px; }
  .pattern-ranking article { grid-template-columns: 48px 1fr; }
  .rank-mark { width: 44px; height: 44px; }
  .rank-board { grid-column: 1 / -1; grid-row: 2; }
  .pattern-ranking article > div:last-child { grid-column: 2; grid-row: 1; }
  .mistake-grid article { padding-left: 64px; }
  .drill-grid { padding: 30px 24px; border-radius: var(--radius-md); }
  .play-hero { padding-top: 36px; }
  .play-hero h1 { font-size: clamp(2.6rem,14vw,4rem); }
  .game-shell { width: 100%; margin-bottom: 30px; }
  .game-stage { padding: 8px; border-radius: 0; }
  .game-topbar { padding-inline: 6px; }
  .game-metrics { gap: 9px; }
  .board-frame { border-radius: 11px; }
  .keyboard-note { display: none; }
  .game-action-row { position: sticky; z-index: 20; bottom: calc(8px + env(safe-area-inset-bottom)); margin: 8px 0; padding: 5px; border-radius: 14px; background: rgba(24,26,39,.93); backdrop-filter: blur(10px); }
  .game-button { min-height: 48px; padding: 0 8px; }
  .game-sidebar { display: flex; }
  .control-card { padding: 15px; }
  .install-card { margin-bottom: calc(4px + env(safe-area-inset-bottom)); }
  .guide-grid article { padding: 24px 18px; }
  .ai-level-card { min-height: 260px; }
  .ai-level-card h3 { margin-top: 58px; }
  .course-tabs a { flex-direction: column; gap: 2px; min-height: 62px; font-size: .68rem; }
  .course-overview { padding-top: 48px; }
  .lesson-card { grid-template-columns: 40px 1fr; gap: 12px; padding: 22px 16px; }
  .lesson-number i { height: 120px; }
  .lesson-content h3 { font-size: 1.12rem; }
  .lesson-complete { grid-column: 1 / -1; justify-self: stretch; }
  .challenge-grid { grid-template-columns: 1fr; padding: 28px 20px; }
  .challenge-grid ul, .challenge-grid > .button { grid-column: 1; }
  .challenge-mark { width: 56px; height: 56px; }
  .hub-content { padding: 42px 20px; }
  .hub-brand { margin-bottom: 50px; }
  .hub-content h1 { font-size: clamp(3rem,15vw,4.8rem); }
  .language-card-grid a { grid-template-columns: 40px 1fr 20px; padding: 12px; }
  .language-card-grid a > span { width: 38px; height: 38px; }
}

@media (max-width: 390px) {
  .game-action-row span { font-size: .68rem; }
  .segmented span { font-size: .62rem; }
  .hero-stats span { font-size: .63rem; }
  .record-grid strong { font-size: .9rem; }
}