:root{--ink: #1f2a30;--ink2: #5a6b73;--bg: #f6f4ef;--card: #ffffff;--brand: #0f4c5c;--brand2: #147d94;--accent: #e36414;--gold: #d9a404;--green: #2a9d5c;--red: #d64545;--blue: #3573c4;--purple: #7b5cc4;--line: #e5e0d5;--radius: 16px;--shadow: 0 2px 10px rgba(31, 42, 48, .07)}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}html,body{margin:0;padding:0}body{background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,PingFang SC,Hiragino Sans GB,Microsoft YaHei,sans-serif;font-size:16px;line-height:1.7}#root{max-width:720px;margin:0 auto;min-height:100vh}.page{padding:0 14px 90px}button{font-family:inherit}.topbar{position:sticky;top:0;z-index:50;background:var(--brand);color:#fff;padding:12px 16px;display:flex;align-items:center;gap:10px;border-radius:0 0 var(--radius) var(--radius)}.topbar .back{background:#ffffff26;color:#fff;border:none;border-radius:10px;padding:6px 12px;font-size:14px;cursor:pointer}.topbar 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0}.chart-caption{font-size:13px;color:var(--ink2);margin-top:8px;text-align:center}.chart-hint{font-size:12.5px;color:var(--accent);font-weight:600;text-align:center;margin-bottom:6px}svg{touch-action:none;-webkit-user-select:none;user-select:none;display:block}.ctrl-row{display:flex;align-items:center;gap:10px;margin:10px 2px;font-size:14px}.ctrl-row label{flex-shrink:0;font-weight:600;color:var(--ink2);font-size:13.5px}input[type=range]{flex:1;accent-color:var(--brand2);height:28px}.toggle-group{display:flex;gap:8px;flex-wrap:wrap;margin:10px 0}.toggle-btn{border:1.5px solid var(--line);background:#fff;color:var(--ink2);border-radius:999px;padding:6px 14px;font-size:13.5px;font-weight:600;cursor:pointer}.toggle-btn.on{background:var(--brand2);border-color:var(--brand2);color:#fff}.readout{display:flex;flex-wrap:wrap;gap:8px;margin-top:8px}.readout .chip{font-size:12.5px;font-weight:700;border-radius:8px;padding:4px 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20px;font-size:15px;font-weight:700;cursor:pointer;width:100%}.primary-btn:disabled{opacity:.4}.ghost-btn{background:none;border:2px solid var(--brand2);color:var(--brand2);border-radius:12px;padding:9px 18px;font-size:14px;font-weight:700;cursor:pointer;width:100%}.quiz-progress{font-size:13px;color:var(--ink2);font-weight:700;margin-bottom:6px}.score-ring{text-align:center;padding:10px 0}.score-big{font-size:42px;font-weight:800;color:var(--brand)}.weak-chip{display:inline-block;background:#fdefef;color:var(--red);border-radius:999px;padding:4px 12px;font-size:13px;font-weight:700;margin:4px 4px 0 0;cursor:pointer}.ok-chip{display:inline-block;background:#ecf8f1;color:var(--green);border-radius:999px;padding:4px 12px;font-size:13px;font-weight:700;margin:4px 4px 0 0}.bottom-nav{position:fixed;bottom:0;left:50%;transform:translate(-50%);width:100%;max-width:720px;background:#fff;display:flex;border-top:1px solid var(--line);z-index:60;padding-bottom:env(safe-area-inset-bottom)}.bottom-nav button{flex:1;background:none;border:none;padding:9px 0 7px;font-size:11.5px;color:var(--ink2);cursor:pointer;font-weight:600}.bottom-nav button.on{color:var(--brand2)}.bottom-nav .icon{font-size:20px;display:block;margin-bottom:1px}.placeholder-row{display:flex;align-items:center;gap:12px;padding:12px 14px;margin:9px 0;border:1.5px dashed var(--line);border-radius:14px;color:var(--ink2);font-size:14px}.footer-note{text-align:center;font-size:12px;color:#a3a89f;margin:26px 0 10px}