:root{color-scheme:light dark;--bg: #f6f6f3;--card: #ffffff;--border: #dedcd5;--text: #1f2328;--muted: #6b7280;--accent: #1c7ed6;--c-text: #1f2328;--c-muted: #6b7280;--c-node: #868e96;--c-node-bg: #ffffff;--c-new: #e8590c;--c-new-bg: #fff0e6;--c-shared: #1c7ed6;--c-shared-bg: #e7f1fb;--c-dropped: #c92a2a;--c-dropped-bg: #fdecec;--c-path: #2f9e44}@media(prefers-color-scheme:dark){:root{--bg: #15171c;--card: #1e2128;--border: #343842;--text: #e6e6e6;--muted: #9aa0a6;--accent: #74c0fc;--c-text: #e6e6e6;--c-muted: #9aa0a6;--c-node: #868e96;--c-node-bg: #23262d;--c-new: #ff922b;--c-new-bg: #3a2514;--c-shared: #74c0fc;--c-shared-bg: #162a3a;--c-dropped: #ff8787;--c-dropped-bg: #3a1c1c;--c-path: #69db7c}}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font:14px/1.55 system-ui,-apple-system,Segoe UI,PingFang SC,Noto Sans CJK SC,sans-serif}code{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.92em;background:color-mix(in srgb,var(--muted) 14%,transparent);padding:1px 6px;border-radius:4px}.top{padding:18px 20px 6px}.top h1{margin:0;font-size:20px;font-weight:600}.sub{margin:4px 0 0;color:var(--muted)}.layout{display:grid;grid-template-columns:230px minmax(0,1fr) 230px;gap:14px;padding:14px 20px 28px;align-items:start}@media(max-width:1100px){.layout{grid-template-columns:220px minmax(0,1fr)}.history{grid-column:1 / -1}}@media(max-width:720px){.layout{grid-template-columns:minmax(0,1fr);padding:12px 16px 24px}}.card{background:var(--card);border:1px solid var(--border);border-radius:10px;padding:12px 14px}.controls fieldset{border:0;margin:0 0 14px;padding:0}.controls legend{font-size:12px;font-weight:600;color:var(--muted);letter-spacing:.04em;padding:0;margin-bottom:6px}.controls label{display:flex;flex-direction:column;gap:3px;margin-bottom:8px;font-size:12.5px;color:var(--muted)}input,select,button{font:inherit;color:var(--text)}input,select{background:var(--bg);border:1px solid var(--border);border-radius:6px;padding:5px 8px;width:100%}.btns{display:grid;grid-template-columns:1fr 1fr;gap:6px}button{background:var(--card);border:1px solid var(--border);border-radius:6px;padding:6px 8px;cursor:pointer;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:12.5px}button:hover{border-color:var(--accent)}button:active{background:color-mix(in srgb,var(--accent) 14%,var(--card))}button:focus-visible,input:focus-visible,select:focus-visible{outline:2px solid var(--accent);outline-offset:1px}button.wide{grid-column:1 / -1}#reset{width:100%}.note{margin:6px 0 0;font-size:12px;color:var(--muted)}.error{margin:0;min-height:1.4em;color:var(--c-dropped);font-size:12.5px}.toolbar{margin-bottom:10px}.tb-row{display:flex;flex-wrap:wrap;align-items:flex-end;gap:10px 14px}.tb-row label{display:flex;flex-direction:column;gap:3px;font-size:12.5px;color:var(--muted)}.tb-mode select{min-width:170px}.tb-speed-row{display:flex;align-items:center;gap:8px;height:31px}.tb-speed input[type=range]{width:140px;padding:0}.tb-speed output{min-width:3ch;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;color:var(--text)}button.primary{min-width:92px;border-color:var(--accent);background:color-mix(in srgb,var(--accent) 12%,var(--card))}button.primary[aria-pressed=true]{background:color-mix(in srgb,var(--accent) 28%,var(--card))}.toolbar .note{margin:8px 0 0}.toolbar .status{margin:4px 0 0;font-size:12.5px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;color:var(--text)}.legend{display:flex;flex-wrap:wrap;gap:6px 16px;margin-bottom:10px;font-size:12.5px}.legend .muted{color:var(--muted)}.sw{display:inline-block;width:14px;height:14px;border-radius:4px;border:1.5px solid;vertical-align:-2px;margin-right:6px}.sw.new{border-color:var(--c-new);background:var(--c-new-bg)}.sw.shared{border-color:var(--c-shared);background:var(--c-shared-bg)}.sw.dropped{border-color:var(--c-dropped);background:var(--c-dropped-bg);border-style:dashed}.sw.path{border-color:var(--c-path);border-width:3px;background:transparent}#panels{display:flex;flex-direction:column;gap:10px}.panel{background:var(--card);border:1px solid var(--border);border-radius:10px;padding:10px 12px 8px;min-width:0}.panel h3{margin:0;font-size:13.5px;font-weight:600}.panel .stats{margin:2px 0 6px;font-size:12px;color:var(--muted)}.panel .scroll{overflow-x:auto}.panel canvas{display:block}.explain{margin-top:10px}.explain h2{margin:0 0 2px;font-size:14px}.explain .hint{margin:0 0 8px;color:var(--muted);font-size:12.5px}.explain ol{margin:0;padding-left:20px}.explain li{margin:2px 0}.explain .result{margin:8px 0 0;font-weight:600}.rules{margin-top:10px}.rules summary{cursor:pointer;font-weight:600}.rules ul{margin:8px 0 0;padding-left:18px}.rules li{margin:4px 0}.history h2{margin:0;font-size:14px}.history ol{position:relative;list-style:none;margin:8px 0 0;padding:0;display:flex;flex-direction:column;gap:4px;max-height:560px;overflow-y:auto}.history li button{width:100%;text-align:left;font-family:inherit;font-size:12.5px;display:block}.history li button .parent{color:var(--muted);font-size:11.5px}.history li button[aria-current=true]{border-color:var(--accent);background:color-mix(in srgb,var(--accent) 12%,var(--card))}