:root{--bg:#f6f7f9;--surface:#fff;--ink:#1a1c20;--ink-soft:#5b616e;--line:#c8ccd4;--line-strong:#3a3f4b;--accent:#2f6bff;--accent-soft:#dbe6ff;--given:#1a1c20;--entry:#2f6bff;--peer:#eef1f6;--same:#d7e6ff;--conflict:#ffd9d9;--conflict-ink:#c0271e;--step:#ffe9b3;--win:#d6f5df;--radius:10px;font-synthesis:none}@media (prefers-color-scheme:dark){:root{--bg:#14161a;--surface:#1d2026;--ink:#e9ecf1;--ink-soft:#9aa1ad;--line:#333844;--line-strong:#6b7280;--accent:#5b8cff;--accent-soft:#24304d;--given:#e9ecf1;--entry:#7aa2ff;--peer:#23272f;--same:#2a3852;--conflict:#4a2523;--conflict-ink:#ff9a92;--step:#4a3f22;--win:#23402d}}:root[data-theme=dark]{--bg:#14161a;--surface:#1d2026;--ink:#e9ecf1;--ink-soft:#9aa1ad;--line:#333844;--line-strong:#6b7280;--accent:#5b8cff;--accent-soft:#24304d;--given:#e9ecf1;--entry:#7aa2ff;--peer:#23272f;--same:#2a3852;--conflict:#4a2523;--conflict-ink:#ff9a92;--step:#4a3f22;--win:#23402d}:root[data-theme=light]{--bg:#f6f7f9;--surface:#fff;--ink:#1a1c20;--ink-soft:#5b616e;--line:#c8ccd4;--line-strong:#3a3f4b;--accent:#2f6bff;--accent-soft:#dbe6ff;--given:#1a1c20;--entry:#2f6bff;--peer:#eef1f6;--same:#d7e6ff;--conflict:#ffd9d9;--conflict-ink:#c0271e;--step:#ffe9b3;--win:#d6f5df}*{box-sizing:border-box}body{background:var(--bg);color:var(--ink);margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;line-height:1.5}.app{width:100%;min-width:0;max-width:940px;margin:0 auto;padding:24px 16px 48px}.app__header h1{margin:0 0 6px;font-size:clamp(1.3rem,3vw,1.8rem)}.app__subtitle{color:var(--ink-soft);max-width:60ch;margin:0 0 18px}.tabs{border-bottom:1px solid var(--line);flex-wrap:wrap;gap:6px;display:flex}.tabs__tab{color:var(--ink-soft);cursor:pointer;background:0 0;border:none;border-bottom:2px solid #0000;margin-bottom:-1px;padding:10px 14px;font-size:.95rem}.tabs__tab:hover{color:var(--ink)}.tabs__tab--active{color:var(--accent);border-bottom-color:var(--accent);font-weight:600}.tabs__tab:focus-visible,.btn:focus-visible,.pad__key:focus-visible,.cell:focus-visible,input:focus-visible{outline:3px solid color-mix(in srgb, var(--accent) 55%, transparent);outline-offset:2px}.app__main{padding:22px 0}.mode{grid-template-columns:minmax(0,1fr) minmax(0,320px);align-items:start;gap:28px;min-width:0;display:grid}.mode--bench{grid-template-columns:minmax(0,1fr)}@media (width<=720px){.app{padding-top:16px}.tabs{gap:2px}.tabs__tab{padding:9px 8px;font-size:.88rem}.mode{grid-template-columns:minmax(0,1fr);gap:20px}}.mode__board,.mode__panel{min-width:0}.mode__board{position:relative}.board{aspect-ratio:1;border:2.5px solid var(--line-strong);background:var(--surface);-webkit-user-select:none;user-select:none;border-radius:6px;grid-template-columns:repeat(9,1fr);width:100%;max-width:480px;display:grid;overflow:hidden}.cell{border:.5px solid var(--line);background:var(--surface);color:var(--given);cursor:pointer;aspect-ratio:1;justify-content:center;align-items:center;padding:0;font-size:clamp(1rem,4.2vw,1.6rem);transition:background 80ms;display:flex;position:relative}.cell--box-left{border-left:2px solid var(--line-strong)}.cell--box-top{border-top:2px solid var(--line-strong)}.cell--given{font-weight:700}.cell__value{color:inherit}.cell--given .cell__value{color:var(--given)}.cell:not(.cell--given) 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var(--line);color:var(--ink-soft);border-radius:999px;padding:3px 10px;font-size:.8rem}.tag--time{font-variant-numeric:tabular-nums}.pad{grid-template-columns:repeat(9,minmax(0,1fr));gap:4px;min-width:0;display:grid}.pad__key{aspect-ratio:1;border:1px solid var(--line);background:var(--surface);color:var(--ink);cursor:pointer;border-radius:8px;min-width:0;padding:0;font-size:1.1rem}.pad__key:hover{border-color:var(--accent);color:var(--accent)}.btn{border:1px solid var(--line);background:var(--surface);color:var(--ink);cursor:pointer;border-radius:8px;padding:8px 12px;font-size:.9rem}.btn:hover:not(:disabled){border-color:var(--accent)}.btn:disabled{opacity:.45;cursor:default}.btn--on{background:var(--accent-soft);border-color:var(--accent);color:var(--accent)}.btn--level{flex:1;min-width:64px}.btn--primary{background:var(--accent);color:#fff;border-color:var(--accent);font-weight:600}.lead-text{color:var(--ink-soft);margin:0;font-size:.9rem}.hint-text{color:var(--ink-soft);margin:4px 0 0;font-size:.82rem}.status{background:var(--accent-soft);border-radius:8px;margin:0;padding:8px 10px;font-size:.84rem}.status--error{background:var(--conflict);color:var(--conflict-ink)}.field{color:var(--ink-soft);flex-direction:column;gap:4px;font-size:.85rem;display:flex}.field input[type=number]{border:1px solid var(--line);background:var(--surface);color:var(--ink);border-radius:8px;width:120px;padding:7px 10px}.field--check{flex-direction:row;align-items:center;gap:8px}.stats{grid-template-columns:repeat(2,1fr);gap:8px;margin:0;display:grid}.stats>div{background:var(--surface);border:1px solid var(--line);border-radius:8px;padding:8px 10px}.stats dt{color:var(--ink-soft);margin:0;font-size:.75rem}.stats dd{font-variant-numeric:tabular-nums;margin:2px 0 0;font-size:1.1rem;font-weight:600}.grid-string{word-break:break-all;color:var(--ink-soft);background:var(--surface);border:1px solid 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th{color:var(--ink-soft);font-weight:600}.cell-warn{color:var(--conflict-ink);font-weight:600}.app__footer{border-top:1px solid var(--line);color:var(--ink-soft);flex-wrap:wrap;gap:10px;margin-top:32px;padding-top:16px;font-size:.85rem;display:flex}.app__footer a{color:var(--accent);text-decoration:none}.app__footer a:hover{text-decoration:underline}