:root{--bg:#f1f5f9;--surface:#fff;--text:#0f172a;--muted:#64748b;--line:#e2e8f0;--primary:#1d4ed8;--primary-dark:#1e3a8a;--primary-soft:#dbeafe;--ok:#15803d;--ok-soft:#dcfce7;--bad:#b91c1c;--bad-soft:#fee2e2;--warn:#b45309;--warn-soft:#fef3c7;--radius:14px;--tap:48px;--nav-h:68px}*,:after,:before{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{background:var(--bg);color:var(--text);-webkit-tap-highlight-color:transparent;margin:0;font:16px/1.55 system-ui,-apple-system,Segoe UI,Roboto,sans-serif}h1,h2{margin:0 0 .5rem;line-height:1.25}h1{font-size:1.5rem}h2{font-size:1.1rem}p{margin:0 0 .75rem}ul{margin:0;padding:0;list-style:none}a{text-decoration:none}a,button{color:inherit}button{font:inherit}:focus-visible{outline-offset:2px;outline:3px solid #93c5fd}.muted{color:var(--muted)}.small{font-size:.85rem}.ok{color:var(--ok)}.bad{color:var(--bad)}.page{width:100%;max-width:560px;padding:16px 16px 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#cbd5e1;border-radius:10px;min-height:44px;font-weight:600}.num--answered{background:var(--primary);border-color:var(--primary);color:#fff}.num--flagged{color:#fff;background:#f59e0b;border-color:#f59e0b}.num--current{outline-offset:1px;outline:3px solid #1e293b}.legend{color:var(--muted);flex-wrap:wrap;gap:6px 14px;font-size:.82rem;display:flex}.legend li{align-items:center;gap:6px;display:flex}.legend .num{cursor:default;border-radius:4px;width:16px;height:16px;min-height:16px;display:inline-block}.modal{z-index:60;background:#0f172a80;place-items:end center;padding:12px;display:grid;position:fixed;inset:0}.modal__box{width:100%;max-width:420px}.summary{gap:4px;margin:10px 0;display:grid}.modal__actions{margin-top:14px}.modal__actions .btn,.result__actions .btn{flex:1}.toast{left:14px;right:14px;bottom:calc(16px + var(--nav-h) + env(safe-area-inset-bottom));z-index:70;color:#fff;background:#1e293b;border-radius:12px;max-width:420px;margin:0 auto;padding:12px 16px;font-size:.92rem;position:fixed}.result,.toast{text-align:center}.result__score{justify-content:center;align-items:baseline;gap:6px;margin:4px 0 10px;display:flex}.result__score strong{color:var(--primary);font-size:3.2rem;line-height:1}.result__score span{color:var(--muted);font-size:1.1rem}.stats{grid-template-columns:repeat(3,1fr);gap:8px;margin:16px 0;display:grid}.stats li{border:1px solid var(--line);background:#f8fafc;border-radius:12px;padding:10px;font-size:.85rem}.stats strong{font-size:1.4rem;display:block}.topics{gap:12px;margin-top:10px;display:grid}.topics .row{align-items:flex-start;gap:12px;margin-bottom:4px}.topics__name{font-size:.9rem}.section-title{margin:6px 2px 8px}.tabs{background:var(--bg);z-index:5;gap:6px;padding-top:6px;padding-bottom:8px;display:flex;position:sticky;top:0;overflow-x:auto}.tab{border:1px solid var(--line);cursor:pointer;background:#fff;border-radius:999px;flex:none;min-height:40px;padding:0 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