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0;font-size:1.0625rem;line-height:1.65}.prose>*+*{margin-top:1em}.prose h2{font-size:1.5rem;font-weight:750;margin-top:2.1em}.prose h2+*{margin-top:.6em}.prose ul,.prose ol{padding-left:1.3em}.prose li+li{margin-top:.4em}.prose li::marker{color:var(--brand);font-weight:700}.prose strong{font-weight:700}.data-table{width:100%;border-collapse:collapse;font-variant-numeric:tabular-nums;font-size:.9375rem}.data-table caption{text-align:left;color:var(--ink-2);font-size:.875rem;padding-bottom:6px}.data-table th,.data-table td{text-align:left;padding:8px 10px;border-bottom:1px solid var(--line)}.data-table td:last-child,.data-table th:last-child{text-align:right}.next-step{margin-top:2em}.legend{list-style:none;padding:0!important;display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:0 28px}.legend li{display:flex;align-items:center;gap:14px;padding:10px 0;border-bottom:1px solid var(--line);margin:0!important}.legend-tile{--cell: 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16px;color:var(--ink-2)}.related{max-width:68ch;margin:48px auto 0}.related h2{font-size:1.125rem;font-weight:750;margin-bottom:10px}.related div{display:grid;grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:10px}.related a{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:14px 16px;border-radius:12px;background:var(--surface);border:1.5px solid var(--line-strong);box-shadow:0 3px 0 var(--line-strong);color:var(--ink);font-weight:650;text-decoration:none;transition:transform .12s var(--ease),box-shadow .12s var(--ease)}.related a:hover{border-color:var(--brand)}.related a:active{transform:translateY(2px);box-shadow:0 1px 0 var(--line-strong)}.related .icon{color:var(--brand)}.static-board{--cell: 56px;--gap: 6px;display:inline-grid;grid-template-columns:repeat(var(--n),var(--cell));gap:var(--gap);padding:var(--gap);background:var(--tray);border-radius:12px;box-shadow:0 5px 0 var(--tray-edge)}.static-board .cell{width:var(--cell);height:var(--cell);display:grid}.static-board .tile{border-radius:7px;box-shadow:inset 0 2px #fff6,0 3px 0 var(--t-edge)}.static-board .tile.is-highlight{outline:3px solid var(--focus);outline-offset:1px}@media(max-width:400px){.static-board{--cell: 50px;--gap: 5px}}.drills{display:grid;gap:20px;max-width:900px;margin:0 auto}.drill{margin:0;display:grid;grid-template-columns:auto 1fr;gap:24px;align-items:start;padding:20px;background:var(--surface);border:1px solid var(--line);border-radius:14px}@media(max-width:640px){.drill{grid-template-columns:1fr;justify-items:center;padding:16px}.drill figcaption{width:100%}}.drill-question{font-weight:600;font-size:1.0625rem}.drill-number{display:block;color:var(--brand);font-size:.8125rem;font-weight:700;margin-bottom:4px}.drill-choices{display:flex;gap:8px;margin-top:14px}.drill-choice{width:52px;height:48px;border-radius:10px;border:1.5px solid var(--line-strong);background:var(--surface);box-shadow:0 3px 0 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strong{white-space:nowrap}}.lang-switch{display:inline-grid;place-items:center;min-width:44px;height:36px;padding:0 10px;margin-right:2px;border-radius:9px;border:1.5px solid var(--line);color:var(--ink-2);font-weight:650;font-size:.875rem;text-decoration:none}.lang-switch:hover{color:var(--ink);border-color:var(--line-strong)}:lang(ja) .prose{line-height:1.85}:lang(ja) h1,:lang(ja) h2,:lang(ja) h3{letter-spacing:0}:lang(ja) .nav-single .nav-dropdown{display:grid;grid-template-columns:1fr;min-width:220px}@media(min-width:720px){:lang(ja) .nav-menu[data-menu=play].nav-single .nav-dropdown{right:auto;left:0;min-width:220px;grid-template-columns:1fr}}:lang(ja) .versions div{grid-template-columns:repeat(2,1fr)}:lang(ja) .versions a{white-space:nowrap}.lang-switch{display:block;min-width:0;height:auto;margin:0;border:0}.lang-menu{position:relative}.lang-menu>summary{display:inline-flex;align-items:center;gap:5px;height:36px;padding:0 10px;margin-right:2px;border-radius:9px;border:1.5px solid var(--line);color:var(--ink-2);font-weight:650;font-size:.875rem;cursor:pointer;list-style:none}.lang-menu>summary::-webkit-details-marker{display:none}.lang-menu>summary .icon{width:16px;height:16px}.lang-menu>summary:hover,.lang-menu[open]>summary{color:var(--ink);border-color:var(--line-strong)}.lang-dropdown{position:absolute;right:0;top:calc(100% + 6px);z-index:var(--z-dropdown);min-width:150px;padding:6px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-m);box-shadow:0 6px color-mix(in oklab,var(--ink) 8%,transparent)}.lang-dropdown a{padding:9px 12px;border-radius:8px;color:var(--ink);text-decoration:none;font-weight:600}.lang-dropdown a:hover{background:var(--surface-2)}.lang-bar{display:flex;align-items:center;gap:2px;margin-right:4px;padding:3px;border-radius:10px;background:var(--surface-2)}.lang-bar .lang-switch,.lang-current{display:inline-grid;place-items:center;min-width:32px;height:30px;padding:0 6px;border-radius:7px;font-size:.8125rem;font-weight:700;letter-spacing:.02em;text-decoration:none;color:var(--ink-2)}.lang-bar .lang-switch:hover{color:var(--ink);background:var(--surface)}.lang-current{background:var(--surface);color:var(--ink);box-shadow:0 1px 0 var(--line-strong)}@media(max-width:380px){.lang-bar .lang-switch,.lang-current{min-width:28px;padding:0 4px}.header-inner{gap:4px;padding-right:8px}.brand-name{font-size:1.0625rem}}@media(min-width:720px){.header-inner{display:grid;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr);padding-inline:16px}.header-actions{justify-self:end}.nav-menu[data-menu=play]{position:static}.nav-menu[data-menu=play] .nav-dropdown{left:50%;right:auto;transform:translate(-50%);min-width:600px}}.lang-menu>summary{min-height:44px}.lang-dropdown .lang-switch,.lang-dropdown .lang-current{display:flex;align-items:center;min-height:44px;width:100%;padding:9px 12px;font-size:.9375rem;box-shadow:none}.lang-dropdown .lang-current{background:var(--brand-soft)}.lang-menu[open]>summary .icon{transform:rotate(180deg)}.nav-group-toggle,.lang-mobile-label{display:none}@media(max-width:719px){.main-nav>.lang-menu{border-bottom:1px solid var(--line);padding-bottom:8px;margin-bottom:6px}.main-nav>.lang-menu>summary{display:flex;justify-content:space-between;width:100%;margin:0;min-height:48px}.main-nav .lang-desktop-label{display:none}.main-nav .lang-mobile-label{display:inline}.main-nav .lang-dropdown{position:static;min-width:0;margin-top:6px;box-shadow:none}.main-nav{max-height:calc(100dvh - 56px);overflow-y:auto;overscroll-behavior:contain;padding-bottom:max(14px,env(safe-area-inset-bottom))}.nav-grouped .nav-dropdown{grid-template-columns:1fr}.nav-group:has(.nav-group-toggle) .nav-group-title{display:none}.nav-group-toggle{display:flex;align-items:center;justify-content:space-between;width:100%;min-height:48px;padding:8px 12px;border:0;background:var(--surface-2);color:var(--ink);font:inherit;font-weight:650;border-radius:8px;cursor:pointer}.nav-group{margin-bottom:6px}.nav-group-toggle[aria-expanded=false]+.nav-group-links{display:none}.nav-group-toggle[aria-expanded=true] .icon{transform:rotate(180deg)}.nav-dropdown a,.nav-link{min-height:44px}.nav-grouped .nav-dropdown a{padding:10px 16px}.brand{gap:6px}.brand-name{display:inline}}