:root{font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:#253a35;background:#f4f5ed;font-synthesis:none;--green:#285b4c;--muted:#6a7972;--wood:#eddbb6;--ink:#24342f}*{box-sizing:border-box}body{margin:0}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer}button:disabled{cursor:default;opacity:.45}a{color:var(--green);text-underline-offset:3px}button:focus-visible,a:focus-visible{outline:3px solid #e08c43;outline-offset:4px}[hidden]{display:none!important}.shell{width:min(1160px,calc(100% - 64px));margin:auto}.skip{position:fixed;top:-80px;left:16px;z-index:5;padding:12px;background:#fff}.skip:focus{top:16px}.top{display:flex;align-items:center;justify-content:space-between;min-height:100px;gap:20px}.logo{display:flex;gap:9px;align-items:center;font-size:18px;font-weight:750;text-decoration:none;color:var(--ink)}.logo img{width:30px;height:30px}nav{display:flex;gap:24px;font-size:14px}nav a{text-decoration:none}.hero{padding:32px 0 36px}.eyebrow{font-size:12px;letter-spacing:.2em;text-transform:uppercase;color:var(--green);font-weight:800;margin:0 0 12px}h1{font-size:clamp(30px,4.5vw,54px);font-weight:650;letter-spacing:-.055em;line-height:1.08;margin:0 0 16px}.hero>p:last-child{color:var(--muted);margin:0;max-width:540px;line-height:1.6;font-size:17px}.workspace{display:grid;grid-template-columns:minmax(0,740px) minmax(230px,1fr);gap:32px;align-items:start}.game-card{background:#fff;border:1px solid #e1e5d8;border-radius:24px;padding:28px;box-shadow:0 12px 35px #253a3506}.game-head{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:24px}.game-head h2{font-size:17px;font-weight:650;margin:0;white-space:nowrap}.segmented{display:flex;gap:3px;background:#edf0e7;padding:4px;border-radius:12px}.segmented button{border:0;border-radius:9px;padding:10px 13px;min-height:40px;color:var(--muted);background:none;font-size:13px;font-weight:600}.segmented button[aria-pressed=true]{background:#fff;color:var(--green);box-shadow:0 1px 5px #16352813}.board-frame{position:relative;background:var(--wood);border:1px solid #d7c49d;border-radius:16px;padding:18px;box-shadow:inset 0 0 0 5px #f4e5c7}.board{display:grid;grid-template-rows:repeat(15,1fr);aspect-ratio:1;position:relative;width:100%;isolation:isolate}.grid-row{display:grid;grid-template-columns:repeat(15,minmax(0,1fr));min-height:0}.point{border:0;padding:0;background:transparent;position:relative;min-width:0;min-height:0;aspect-ratio:1;isolation:isolate;outline-offset:-2px!important}.point:before{content:"";position:absolute;left:50%;top:var(--vertical);width:1px;height:var(--height);background:#7d765d;opacity:.62;z-index:-1}.point:after{content:"";position:absolute;top:50%;left:var(--horizontal);height:1px;width:var(--width);background:#7d765d;opacity:.62;z-index:-1}.point[data-star]:not(.black):not(.white) .stone{opacity:1;width:13%;height:13%;background:#746a50;box-shadow:none}.stone{position:absolute;width:79%;height:79%;border-radius:50%;left:50%;top:50%;transform:translate(-50%,-50%);opacity:0;pointer-events:none}.black .stone{opacity:1;background:radial-gradient(circle at 32% 26%,#5c625c,#2a342e 56%,#19231e);box-shadow:0 2px 3px #27302a40}.white .stone{opacity:1;background:radial-gradient(circle at 34% 27%,#fff,#f0f0e5 65%,#c9cbbd);border:1px solid #abb3a055;box-shadow:0 2px 3px #27302a35}.last .stone:after{content:"";position:absolute;left:42%;top:42%;width:16%;height:16%;border-radius:50%;background:#dba669}.winning .stone{outline:3px solid #bf7a36;outline-offset:2px}.point:not(.black):not(.white):not([aria-disabled=true]):hover .stone{opacity:.3;width:70%;height:70%;background:#285b4c}.board-meta{display:flex;gap:12px;justify-content:space-between;align-items:center;flex-wrap:wrap;margin:18px 0 22px;font-size:14px}.board-meta>span:first-child{font-weight:650}.board-meta .counts{display:flex;gap:18px;color:var(--muted);font-size:13px}.tools{display:flex;gap:10px;flex-wrap:wrap}.tools button,.save-problem button,dialog button{min-height:44px;padding:10px 17px;border:1px solid #dbe1d3;background:#fff;color:var(--green);border-radius:10px;font-weight:650;font-size:13px}.tools .primary,dialog .primary{background:var(--green);color:#fff;border-color:var(--green)}.status{font-size:13px;line-height:1.5;min-height:0;margin:0}.status:not(:empty){margin-top:16px}.status[data-kind=error]{color:#9d4c2d}.rules-card{padding:12px 0}.rules-card img{display:block;width:100%;max-width:300px;margin:0 auto 28px}.rules-card h2,.about h2{font-size:21px;letter-spacing:-.025em;font-weight:650}.rules-card ol{padding-left:22px;color:var(--muted);font-size:14px;line-height:1.7}.rules-card li{padding-left:5px;margin-bottom:13px}.key-help{font-size:12px;color:var(--muted);line-height:1.6;margin:22px 0}.rules-card>a{font-size:13px;font-weight:650}.about{padding:38px 0;max-width:720px}.about p{line-height:1.75;color:var(--muted);font-size:14px}.footer{border-top:1px solid #dce2d3;display:flex;gap:24px;flex-wrap:wrap;padding:25px 0 35px;font-size:12px}.footer a{color:var(--muted)}.save-problem{border:1px solid #e3c894;border-radius:12px;background:#fff9ef;padding:16px;margin-top:18px;font-size:13px;line-height:1.6}.save-problem p{margin-top:0}.save-problem button{margin:0 5px 5px 0}details{font-size:12px;margin-top:12px}summary{cursor:pointer;min-height:32px}pre{white-space:pre-wrap;overflow-wrap:anywhere;font-size:12px}dialog{border:1px solid #dde4d4;border-radius:20px;padding:28px;max-width:430px;width:calc(100% - 32px);color:var(--ink);box-shadow:0 20px 80px #10241d25}dialog::backdrop{background:#23362f60}dialog h2{font-size:21px;margin:0 0 16px}dialog p{font-size:14px;line-height:1.65;color:var(--muted)}dialog form{display:flex;gap:10px;justify-content:flex-end;margin-top:22px}.prose{max-width:720px;margin:20px auto 60px;line-height:1.8}.prose h1{font-size:38px}.prose h2{font-size:22px;margin-top:32px}.prose p,.prose li{font-size:15px;color:var(--muted)}.prose img{max-width:400px;width:100%;display:block;margin:30px 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@media(max-width:850px){.shell{width:calc(100% - 36px)}.workspace{grid-template-columns:minmax(0,1fr);gap:28px}.game-card{max-width:700px;width:100%;margin:auto}.rules-card{display:grid;grid-template-columns:180px 1fr;column-gap:28px}.rules-card img{grid-row:1/5;margin:0}.rules-card h2{margin-top:0}.rules-card ol{margin-top:0}.key-help{margin:0 0 12px}.top{min-height:82px}.hero{padding:24px 0 28px}}
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