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.btn:hover:not(:disabled){border-color:var(--ink);background:transparent}.book-moves .note-move{font-weight:700;min-width:3.5rem}.game-info{margin:0}.form-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:16px 24px}.field{display:flex;flex-direction:column;gap:6px;font-weight:600;font-size:14px}.field select,.field input,.field textarea{font-weight:400;font-size:16px}.table-wrap{overflow-x:auto}.games{width:100%;border-collapse:collapse}.games th{background:var(--canvas-tint);font-size:12px;font-weight:600;text-align:left;padding:10px 12px}.games td{padding:8px 12px;border-bottom:1px solid var(--hairline)}.games td:first-child{width:2.5rem;color:var(--muted)}.gate{min-height:100vh;background:var(--canvas-warm)}.gate-top{display:flex;justify-content:space-between;align-items:center;padding:16px var(--gutter);background:var(--canvas);border-bottom:1px solid var(--hairline)}.gate-main{max-width:720px;margin:0 auto;padding:var(--section) var(--gutter)}.gate-main h1{font-size:40px}.gate-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin-top:32px}.gate-tile{--k: #e21b3c;position:relative;display:flex;flex-direction:column;gap:10px;padding:12px;background:var(--canvas);border:1px solid var(--hairline);border-bottom:6px solid var(--k);border-radius:var(--r-md);cursor:pointer;font:inherit;color:var(--ink);text-align:left;transition:border-color .15s,opacity .2s}.gate-tile.k1{--k: #1368ce}.gate-tile.k2{--k: #d89e00}.gate-tile.k3{--k: #26890c}.gate-tile:hover:not(:disabled){border-color:var(--ink);border-bottom-color:var(--k)}.gate-tile:disabled{cursor:default;opacity:.45}.gate-label{display:flex;align-items:center;gap:10px;min-height:32px}.gate-shape{flex:none;width:32px;height:32px;display:grid;place-items:center;background:var(--k);color:#fff;border-radius:var(--r-xs);font-size:18px;line-height:1}.gate-pic{display:block;aspect-ratio:1;overflow:hidden;border-radius:var(--r-sm);background:var(--canvas-tint)}.gate-pic img{width:100%;height:100%;object-fit:cover;display:block}.gate-fallback{display:grid;place-items:center;height:100%;padding:16px;text-align:center;font-family:var(--serif);font-size:26px}.gate-name{font-weight:700}.gate-tile.wrong{opacity:.55}.gate-tile.right{border-color:var(--forest);box-shadow:inset 0 0 0 2px var(--forest)}.gate-mark{position:absolute;top:20px;right:20px;width:36px;height:36px;display:grid;place-items:center;background:var(--ink);color:var(--canvas);border-radius:50%;font-size:18px}.gate-tile.shake{animation:shake .35s}@keyframes shake{25%{transform:translate(-6px)}50%{transform:translate(6px)}75%{transform:translate(-3px)}}@media (prefers-reduced-motion: reduce){.gate-tile.shake{animation:none}}.gate-foot{min-height:88px;margin-top:24px;display:flex;flex-direction:column;align-items:flex-start;gap:12px}.gate-foot p{margin:0;font-size:17px}.shell.with-chat{display:grid;grid-template-columns:minmax(0,1fr) 380px}@media (min-width: 1101px){.topbar.with-chat{padding-right:380px}}.chat-panel{position:sticky;top:var(--masthead-h);height:calc(100vh - var(--masthead-h));display:flex;flex-direction:column;background:var(--canvas);border-left:1px solid var(--hairline)}.chat-head{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:12px 16px;border-bottom:1px solid var(--hairline)}.chat-head>div:first-child{min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.chat-head-actions{display:flex;gap:6px;flex-shrink:0}.chat-head-actions .btn{white-space:nowrap}.chat-log{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:10px;background:var(--canvas-soft)}.chat-empty{padding:16px;display:flex;flex-direction:column;gap:12px;align-items:flex-start}.chips{display:flex;flex-wrap:wrap;gap:6px}.bubble{border-radius:var(--r-md);padding:10px 14px;max-width:92%;font-size:15px;line-height:1.5;overflow-wrap:anywhere}.bubble p{margin:0 0 6px}.bubble p:last-child{margin-bottom:0}.bubble ul,.bubble ol{margin:4px 0 6px;padding-left:1.2em}.bubble code{background:var(--wash);padding:0 4px;border-radius:var(--r-xs)}.bubble-user{align-self:flex-end;background:var(--primary);color:var(--on-primary)}.bubble-user code{background:#7f7f7f40}.bubble-assistant{align-self:flex-start;background:var(--canvas);border:1px solid var(--hairline)}.typing{color:var(--muted);font-style:italic}.chat-offline{margin:0;padding:8px 16px;background:var(--gold-soft);color:var(--ink);font-size:14px}.chat-input{display:flex;gap:8px;padding:12px 16px 6px;border-top:1px solid var(--hairline);align-items:flex-end}.chat-input textarea{resize:none}.chat-foot{margin:0;padding:0 16px 12px}.tips-body{flex:1;overflow-y:auto;background:var(--canvas-soft)}.tips-section{padding:16px;border-bottom:1px solid var(--divider);font-size:15px;line-height:1.5}.tips-section h3{font-size:15px;margin:0 0 8px}.tips-section h4{font-size:13px;font-weight:700;color:var(--muted);margin:12px 0 4px}.tips-section ul{margin:0;padding-left:1.1em}.tips-section li+li{margin-top:4px}.tips-section p{margin:0 0 6px}.tips-section.principle{background:var(--canvas-warm)}.principle-nav{display:flex;align-items:center;gap:6px;margin-top:8px}.principle-nav .muted{margin-right:auto}details.tips-section summary{cursor:pointer;list-style:none;display:flex;align-items:center;justify-content:space-between}details.tips-section summary::-webkit-details-marker{display:none}details.tips-section summary:after{content:"+";font-weight:700;color:var(--muted)}details.tips-section[open] summary:after{content:"−"}details.tips-section summary h3{margin:0}details.tips-section[open] summary{margin-bottom:10px}.glossary{margin:12px 0 0}.glossary div+div{margin-top:10px}.glossary dt{font-weight:700}.glossary dd{margin:2px 0 0;color:var(--ink)}.tips-foot{padding:16px;margin:0}.support-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px;align-items:stretch}@media (max-width: 1100px){.support-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media (max-width: 600px){.support-grid{grid-template-columns:minmax(0,1fr)}}.support-card{display:flex;flex-direction:column;gap:16px}.support-card img{width:100%;max-width:360px;align-self:center;border-radius:var(--r-md);border:1px solid var(--hairline)}.support-info h2{margin-bottom:4px}.support-number{display:flex;align-items:center;gap:10px;margin:8px 0}.support-number code{font-size:18px;font-weight:700}.learn-modes{margin-top:16px}.opening-card.is-locked{background:var(--canvas-tint)}.terms{display:grid;grid-template-columns:260px minmax(0,1fr);gap:32px;align-items:start}.term-index{position:sticky;top:calc(var(--masthead-h) + 24px);display:flex;flex-direction:column;gap:18px}.term-index h3{font-size:14px;color:var(--muted);margin:0 0 6px}.term-index ul{list-style:none;margin:0;padding:0}.term-index button{width:100%;text-align:left;font:inherit;font-size:15px;background:transparent;border:0;border-radius:var(--r-sm);padding:6px 10px;cursor:pointer;color:var(--ink)}.term-index button:hover{background:var(--canvas-warm)}.term-index button.current{font-weight:700;background:var(--primary);color:var(--on-primary)}.term-body{display:grid;grid-template-columns:minmax(0,560px) minmax(0,1fr);gap:28px;align-items:start}.term-body .term-text{margin-top:0}.term-text{font-size:17px;line-height:1.55}.answer-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.answer{--k: #e21b3c;display:flex;align-items:center;gap:12px;text-align:left;font:inherit;padding:14px;background:var(--canvas);color:var(--ink);border:1px solid var(--hairline);border-bottom:5px solid var(--k);border-radius:var(--r-md);cursor:pointer}.answer.k1{--k: #1368ce}.answer.k2{--k: #d89e00}.answer.k3{--k: #26890c}.answer .gate-shape{background:var(--k)}.answer:hover:not(:disabled){border-color:var(--ink);border-bottom-color:var(--k)}.answer:disabled{opacity:.45;cursor:default}.answer.right{box-shadow:inset 0 0 0 2px var(--forest)}.answer.wrong{box-shadow:inset 0 0 0 2px var(--error)}.elo-big{font-family:var(--serif);font-size:64px;line-height:1;margin:0}.elo-dots{display:flex;gap:6px}.elo-dots span{width:14px;height:14px;border-radius:50%;background:var(--hairline)}.elo-dots span.yes{background:var(--forest)}.elo-dots span.no{background:var(--error)}.elo-dots span.now{box-shadow:inset 0 0 0 2px var(--ink);background:var(--canvas)}.elo-map{list-style:none;margin:0;padding:0}.elo-map li{display:flex;flex-wrap:wrap;align-items:center;gap:4px 12px;padding:8px 12px;color:var(--muted)}.elo-map li.below{color:var(--ink)}.elo-map li.here{background:var(--canvas-warm);color:var(--ink);font-weight:700;border-radius:var(--r-sm)}.elo-num{font-family:var(--mono);min-width:3.5rem}.calc{border-top:1px solid var(--divider);padding-top:16px;margin-top:8px}.calc summary{cursor:pointer;list-style:none}.calc summary::-webkit-details-marker{display:none}.calc summary h3{display:inline;margin:0}.calc summary:after{content:" +";color:var(--muted);font-weight:700}.calc[open] summary:after{content:" −"}.calc .form-grid{margin-top:12px}.calc-out{margin:12px 0 0}.bot-setup .persona-grid{grid-template-columns:repeat(auto-fit,minmax(150px,1fr))}.celebration{position:fixed;top:0;right:0;bottom:0;left:0;width:100vw;height:100vh;pointer-events:none;z-index:200}.list-tools{display:flex;flex-wrap:wrap;align-items:center;gap:12px 20px}.list-tools input[type=search]{max-width:360px}.pager{display:flex;flex-wrap:wrap;align-items:center;gap:6px}.pager button{min-width:40px;font:inherit;font-size:14px;padding:8px 10px;border:1px solid var(--hairline);background:var(--canvas);color:var(--ink);border-radius:var(--r-xs);cursor:pointer}.pager button:hover:not(:disabled){border-color:var(--ink)}.pager-gap{min-width:24px;text-align:center;color:var(--muted)}.pager button.current{background:var(--primary);border-color:var(--primary);color:var(--on-primary)}.pager button:disabled{color:var(--disabled-ink);cursor:default}.notation-layout{margin-top:8px}.san-big{font-family:var(--mono);font-size:32px;font-weight:700;margin-left:6px}.notation-input{display:flex;align-items:center;gap:10px}.notation-input input{font-family:var(--mono);font-size:22px;max-width:220px}.notation-input .move-no{font-family:var(--mono);font-size:20px;min-width:0}.san-parts{list-style:none;margin:10px 0 14px;padding:0;display:flex;flex-direction:column;gap:6px}.san-parts li{display:flex;align-items:baseline;gap:12px}.san-parts code{min-width:3.5rem;font-size:17px;font-weight:700}.sheet{border-collapse:collapse;width:100%}.sheet th,.sheet td{text-align:left;padding:8px 12px;border-bottom:1px solid var(--hairline);vertical-align:baseline}.sheet th{width:8rem;font-weight:400}.sheet code{font-size:16px;font-weight:700}#overview,[id^=phase-]{scroll-margin-top:calc(var(--masthead-h) + 16px)}.gantt-scroll{overflow-x:auto;padding-bottom:4px}.gantt{display:grid;grid-auto-rows:34px;align-items:center;min-width:760px;position:relative}.gantt-head{font-size:12px;font-weight:700;color:var(--muted);padding:0 4px;border-left:1px solid var(--hairline);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;align-self:stretch;display:flex;align-items:center}.gantt-day{font-family:var(--mono);font-size:11px;color:var(--muted)}.gantt-label{font-size:14px;color:var(--ink);padding-right:12px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;position:sticky;left:0;z-index:3;background:var(--canvas);align-self:stretch;display:flex;align-items:center}.gantt-label:hover{text-decoration:underline}.gantt-track{height:100%;border-top:1px solid var(--divider)}.gantt-bar{position:relative;z-index:1;height:18px;border-radius:var(--r-xs);display:flex;align-items:center;justify-content:flex-end;padding:0 6px;overflow:hidden}.gantt-bar.core{background:linear-gradient(90deg,var(--forest) var(--done, 0%),var(--primary) var(--done, 0%))}.gantt-bar.daily{background:repeating-linear-gradient(135deg,var(--gold) 0 6px,var(--gold-soft) 6px 12px)}.gantt-bar.optional{background:transparent;border:2px dashed var(--muted);height:16px}.gantt-pct{font-size:11px;font-weight:700;color:var(--on-primary)}.gantt-mark{position:relative;z-index:1;justify-self:center;color:var(--brand-mark);font-size:15px;line-height:1;text-decoration:none}.gantt-mark:hover{text-decoration:none;transform:scale(1.2)}.gantt-today{z-index:2;align-self:stretch;justify-self:center;width:2px;background:var(--focus);position:relative;pointer-events:none}.gantt-today span{position:absolute;top:42px;right:4px;font-size:11px;font-weight:700;color:var(--focus);white-space:nowrap;background:var(--canvas);padding:0 4px;border-radius:var(--r-xs)}.gantt-legend{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap;gap:8px 24px;font-size:13px;color:var(--muted)}.gantt-legend li{display:flex;align-items:center;gap:8px}.gantt-legend .gantt-bar{width:32px;height:12px;padding:0}.gantt-legend .gantt-bar.core{background:var(--primary)}.site-footer{border-top:1px solid var(--hairline);background:var(--canvas)}.footer-inner{max-width:var(--container);margin:0 auto;padding:32px var(--gutter);display:flex;flex-direction:column;gap:10px}.quote{display:flex;flex-direction:column;gap:4px;align-items:flex-start;text-align:left;font:inherit;background:transparent;border:0;padding:0;cursor:pointer;color:var(--ink)}.quote-text{font-family:var(--serif);font-size:22px;line-height:1.35;max-width:60ch}.quote-author{font-size:14px;color:var(--muted)}.made{margin:6px 0 0;font-weight:600}.brand{text-decoration:none}.brand:hover{text-decoration:none;opacity:.85}.sticky-credit{position:fixed;left:0;right:0;bottom:0;z-index:9;display:flex;justify-content:center;align-items:center;gap:4px;flex-wrap:wrap;padding:6px var(--gutter);font-size:13px;font-weight:600;color:var(--muted);background:var(--canvas);border-top:1px solid var(--hairline);transform:translateY(100%);transition:transform .2s ease;pointer-events:none}.sticky-credit.show{transform:none;pointer-events:auto}.sticky-credit a{color:var(--ink)}@media (prefers-reduced-motion: reduce){.sticky-credit{transition:none}}.suggestions{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:10px}.suggestion{display:flex;align-items:center;gap:14px;height:100%;padding:14px 16px;border-radius:var(--r-md);background:var(--canvas-soft);color:var(--ink);text-decoration:none;transition:background .15s}.suggestion:hover{background:var(--canvas-warm);text-decoration:none}.suggestion-icon{flex:none;width:40px;height:40px;display:grid;place-items:center;border-radius:var(--r-sm);background:var(--canvas);font-size:20px}.suggestion-text{flex:1;display:flex;flex-direction:column;gap:2px;min-width:0}.suggestion-go{color:var(--muted);font-size:18px}.book-cover{--w: 150px;position:relative;flex:none;width:var(--w);height:calc(var(--w) * 1.5);display:flex;flex-direction:column;align-items:center;justify-content:flex-end;gap:calc(var(--w) * .03);padding:0 calc(var(--w) * .08) calc(var(--w) * .14) calc(var(--w) * .16);overflow:hidden;color:#f7f3ee;background:linear-gradient(160deg,#ffffff14,#0000002e),var(--tone);border-radius:3px var(--r-sm) var(--r-sm) 3px;text-align:center;box-shadow:inset -1px 0 #ffffff14}.book-cover.lg{--w: 220px}.book-spine{position:absolute;left:0;top:0;bottom:0;width:9%;background:linear-gradient(90deg,#00000059,#ffffff14 70%,#00000026)}.book-glyph{position:absolute;top:12%;left:0;right:0;padding-left:6%;font-size:calc(var(--w) * .36);line-height:1;color:var(--gold);opacity:.95}.book-sub{font-size:calc(var(--w) * .06);letter-spacing:.12em;text-transform:uppercase;color:#f7f3eeb8}.book-title{font-family:var(--serif);font-size:calc(var(--w) * .12);line-height:1.12}.book-rule{width:28%;height:3px;background:var(--gold);margin:2px 0}.book-author{font-size:calc(var(--w) * .065);color:#f7f3eecc}.shelf{display:grid;gap:16px}.shelf-item{display:flex;gap:28px;align-items:center;padding:24px;background:var(--canvas);border:1px solid var(--hairline);border-radius:var(--r-md);color:var(--ink);text-decoration:none;transition:background .15s}.shelf-item:hover{background:var(--canvas-soft);text-decoration:none}.shelf-item:hover .book-cover{transform:translateY(-3px) rotate(-1deg)}.shelf-item .book-cover{transition:transform .2s ease}.shelf-text{display:flex;flex-direction:column;gap:8px;align-items:flex-start;min-width:0}.shelf-text h2{font-family:var(--serif);font-weight:400;font-size:26px;margin:0}.shelf-text p{margin:0;max-width:70ch}.reader-head{display:flex;gap:32px;align-items:center}.reader-head h1{margin:0}.reader-head .gold-rule{margin:4px 0}.reader-head p{margin:0;max-width:70ch}.flip-stage{position:relative;display:flex;flex-direction:column;gap:18px;padding:40px 24px 20px;border-radius:var(--r-md);background:radial-gradient(ellipse at 50% 35%,var(--canvas-soft),var(--canvas-warm) 75%)}.flip-stage:fullscreen{justify-content:center;padding:24px 32px;overflow:auto;border-radius:0}.flip-area{position:relative;display:flex;align-items:center}.flip-shift{position:relative;flex:1;min-width:0;filter:drop-shadow(0 18px 22px rgba(22,21,19,.22)) drop-shadow(0 2px 4px rgba(22,21,19,.12));transition:transform .6s cubic-bezier(.4,0,.2,1)}.flip-host{width:100%}.flip-host .stf__parent{margin:0 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